A Brief Visual
History of Travel

Populating the Planet

A two million year journey begins

Our story, the history of travel, begins here, with our early ancestors, specifically the type of human known to science as Homo erectus, which lived from about two million years ago up until about 150,000 years ago. Homo erectus was remarkably unique and sophisticated in a number of ways: this was the first type of human to control fire and one of the first to use stone tools. And although we now know the species originated in East Africa, the first fossil discovered was in 1891 in Java, an Indonesian island some 5,000 miles away as the crow flies.

Of course, Homo erectus wasn’t a crow and it couldn’t fly, and although there is some evidence to suggest the species created basic rafts, it certainly didn’t invent anything which could cross thousands of miles of Indian Ocean. The only plausible answer, which has been confirmed by other fossil finds in the last century, is that Homo erectus saw fit to gradually leave Africa and colonise other parts of the world, notably the landmasses of Europe and Asia.

The first of the great human migrations had begun, and so too the history of travel.

It’s a peculiar thought that the human race once comprised several different species: our dazzling egos rarely permit us to imagine any other life form being remotely similar in terms of intelligence – even our own family, so to speak. But the fact is there were many, and all are now extinct apart from one: Homo sapiens, from which every human alive today is a direct descendant.

Like other human species, Homo sapiens – that’s us – originated in Africa, with the earliest fossils dating to approximately 200,000 years ago. And like Homo erectus, we migrated out of Africa and began colonising other parts of the world, with the first intrepid explorers flying the nest about 70,000 years ago.

Unlike Homo erectus, we travelled much further, most notably to Australia and the Americas, which meant that by about 10,000 years ago every major inhabitable landmass on Earth supported human life.

Our willingness to travel and explore had allowed us to populate the planet.

The Rise of Civilisation

Settling down in the Age of Innovation

Ironically, the next phase in the history of travel was sparked by people remaining in one place, abandoning the nomadic, hunter-gatherer lifestyle which had served its purpose so well for hundreds of thousands of years.

The reason for this was the invention of agriculture, otherwise known as the Neolithic Revolution, arguably the most important development in human history to date. It would go on to evolve independently in locations around the world, but the first example we know of was about 10,000 years ago in an area called the Fertile Crescent, which on today’s maps encompasses parts of Egypt, Israel, Jordan, Lebanon, Syria and Iraq.

Map of the Fertile Crescent

The domestication of plants and animals removed the need for people to roam endless landscapes in search of food and water. Small groups of nomadic hunters, free from competition, were able to join together into single, settled societies, which were the seeds of civilisation as we know it.

Suddenly there was a surplus of food, people and, ultimately, time. Humans were no longer just surviving; they were living.

The implications of this were vast, but one particular way which affects our story is the innovation of new technologies which enabled us to better move around.

The Wheel

Rolling into a new era of travel

The use of logs as rollers dates back deeper than we’ll ever know, but the modern wheel – that is, built with spokes, attached to an axle and used specifically for transport – seems to have emerged around 5,000 years ago.

To thank for this we have the people of the Indus Valley Civilisation, who inhabited parts of present-day Afghanistan, Pakistan and India, and formed one of the three earliest civilisations; the other two were Ancient Egypt and Mesopotamia.

Like any good idea, this one quickly spread, though without decent roads to travel on, the world’s oceans and rivers would continue to provide the best surface for long distance journeys.

The Sailboat

Embracing the winds of change

No one knows precisely when the first boats were invented, but the sailboat – a significant improvement on, say, a dugout canoe – probably came into use around the same time as the modern wheel.

The Mesopotamians are credited with its invention, and in any case certainly benefited from it, using it to develop a flourishing trade with neighbouring territories and cementing their place in history as one of the world’s most successful civilisations.

Mesopotamian Sailboat

Mesopotamian flood myth

The sail boat would continue to evolve and develop, and some of the great voyages throughout history would never have been achieved were it not for this type of vessel. It allowed people to traverse vast distances in a way which simply would never have been possible by land.

Other ancient civilisations, such as the Egyptians and Sumerians, would continue to use the sail boat to both establish trading posts and to begin exploring the wider world. Eventually this would culminate in the first mini age of discovery, with Ancient Greek and Carthaginian explorers like Hanno, Nearchus and Hippalus making extraordinarily ambitious voyages to places as far east as the Indian subcontinent and as far north as the British Isles.

Classical Explorers

Voyagers from the ancient world

Although exploration in the ancient world offered few guarantees, if voyagers were fortunate enough to return with their lives, they could also be sure to return with at least one invaluable commodity: knowledge.

The world was an enormous jigsaw puzzle which had to be painstakingly put together, piece by piece, a practice which we know today as cartography – the making of maps.

Depending on how loosely the word ‘map’ is defined, arguably the earliest known example can be found in the caves of Lascaux, near Bordeaux in France. Some of the pre-historic rock art within these caves depict star constellations, which throughout history have provided direction and helped people to navigate. The earliest known printed examples of star maps are the work of a Chinese astronomer called Su Song, who lived in the 11th century.

Lascaux rock art

Su Song's star map

The first maps of planetary geography are difficult to date; there is little consensus regarding precisely when they emerged, and indeed whether some examples are even maps of real terrain as opposed to mythical lands.

It’s generally agreed the earliest surviving attempt at a world map is an engraved clay tablet from the ancient civilisation – and shown from the perspective of – Babylonia, dated to around the 6th century BC.

As time wore on and knowledge of the world increased among civilisations, maps grew from rudimentary reckonings to increasingly accurate depictions on much larger scales. A cartographer called Anaximander is credited with producing the first map (of which no evidence remains) showing the entire world as known to the Ancient Greeks, and his efforts were improved upon over the next few centuries by figures like Hecataeus, Herodotus and Eratosthenes.

Early maps by Hecataeus and Herodotus

In the 2nd century AD the Greco-Egyptian geographer Claudius Ptolemy wrote his Geography, which compiled everything the Romans knew about the world at the time, and was fervently translated by knowledge-hungry civilisations for the next thousand years.

The stars may have given humans direction, but direction alone was not enough: we needed to know what we could expect to find in any given direction, and maps answered that need.

Out of China

Wayfaring dynasties of the East

In the far east of present-day China, on the banks of the Yellow River, a new civilisation had arisen of its own accord, and by about 220 BC it had been unified into a single kingdom – the Qin dynasty.

The first Emperor, one Qin Shi Huang, had rather grander aspirations than establishing colonies and trading posts. He decided he wanted to live forever, so sent his minions off into the East China Sea with the unenviable task of locating the secret of immortality.

The most famous of these voyagers was a man called Xu Fu, who duly went about fulfilling the request in the company of 3,000 virgin children. Between 220 and 210 BC Xu Fu made two expeditions. He returned from the first empty handed. He didn’t return at all from the second one, and is presumed to have lived out the rest of his days on the islands which we now know as Japan.

Zhang Qian

The Qin dynasty was followed by the Han dynasty, one of the rulers of which – Liu Bang – had slightly more grounded ambitions with regards to the outside world. Eager to know what lay in the lands to the west, in 138 BC he dispatched a man called Zhang Qian to find out and report back with information.

Little did Zhang Qian know, but his resulting journey into the heart of Asia would lay the foundations for one of the most important overland trade routes in human history: the Silk Road.

Civilisations to Empires

Expanding to Colonise the planet

As we have seen, many thousands of years ago some humans began to abandon their nomadic existence, settling down into small communities to farm the land rather than roam it. Some of these communities developed into societies. Some of these societies developed into civilisations. And some of these civilisations developed into empires.

Travel led to knowledge, to trade, to unfathomable riches. Ultimately it led to power.

Many empires had sprung up by the start of the first millennium, but there was one in particular that dominates the history books, just as it dominated much of the Western world during its existence: the Roman Empire.

Map of the Roman Empire

As you might imagine, the Roman Empire – the size of which at its height in the 2nd century was unprecedented – cost a fair bit to run. This meant trade was essential, which in turn meant travel was essential, both within and outside the borders.

Furthermore, the Romans weren’t exactly famous for their shy and retiring nature: they were quite partial to a bit of conquest here and there, meaning a decent army was essential. As well as conquering new lands, the army was responsible for protecting territory already gained, which meant soldiers needed to be able to travel through the empire with ease, which in turn meant good infrastructure was essential.

All Roads Lead to Rome

Stitching the Empire Together

The Romans did not invent paved pathways. Civilisations the world over, from the Incas to the Celts, developed these independently. The Romans were not the first to build roads to link settlements. The Minoans, for example, constructed a 50km road through the mountains of Crete in 2000 BC, more than a thousand years before Rome even existed.

The Romans were the first, however, to build long distance roads on a massive scale, and this made their empire the mightiest the world had ever known.

An ancient roman road

Rome was the hub, and great highways radiated out from the ancient city like spokes on a wheel, stitching the entire empire together, from the grassy hillocks of northern England to the burnt deserts of Saudi Arabia.

The Romans were so prolifically effective at facilitating travel within their empire that many of their roads are still clearly visible to this day, and others form the literal foundations for major routes still in use.

This expansive network was clearly helpful for the army, and traders who needed to transport goods, but others benefited too. Super-wealthy Romans built holiday villas in places like Pompeii, Baiae and Capri, and used them for vacations, marking the beginning of leisure travel and development of seaside resorts.

And then there were the early pilgrims, whose impressive journeys introduced an entirely new type of travel.

Mongols on the Move

Genghis Khan and the Silk Routes

While the Muslims were busy fending off the last of the Crusaders from the west, a greater and far more ominous power was rising in the east.

Genghis Khan

By the start of the thirteenth century, a Mongolian man who went by the name Temujin had succeeded in unifying the nomadic tribes of northeast Asia into a single dynasty.

The man became known as Genghis Khan and his dynasty developed over the next few decades into the Mongol Empire, which at its greatest extent in 1279 covered almost 25% of the planet’s land surface.

To this day the Mongol Empire remains the largest contained land empire in the history of the world.

It was also one of the shortest-lived, fragmenting into warring factions a mere 150 years after it emerged, but for those few decades of stability an unprecedented freedom of movement and degree of safety for travellers and traders existed throughout the vast territory.

Map of the Mongol Empire

Historians have termed this period of stability the Pax Mongolica – the literal Latin translation is ‘Mongol Peace’ – and it meant the Silk Road, the collective name for the ancient land trade routes linking Europe and Asia, was fully re-established after centuries of fragmentation and being fraught with danger.

“A maiden bearing a nugget of gold on her head can wander safely through the realm,” was a common saying at the time.

Whether or not a gold-carrying maiden ever did wander through the realm is unclear, but we do know that a Venetian merchant called Marco Polo did.

As we have seen, in 1498 Vasco da Gama, a Portuguese explorer, became the first European to sail around Africa and reach India. The momentous implications of this journey cannot be emphasised enough. Vasco da Gama filled a colossal gap in European maritime knowledge and opened up a whole new era of travel.

Vasco da Gama

The entire voyage took almost two years, during which time da Gama lost two of the four ships in his fleet and more than half of the 170 crew. But he returned a hero, having discovered the fabled Indian spice routes. In the decade that followed, the Portuguese would travel even further east, eventually discovering and conquering the source of the trade, the Spice Islands themselves (today the Maluku Islands) in Indonesia.

It should be said, for the record, that Vasco da Gama, for all his navigational prowess, was a man of exceptional cruelty. Driven by his desire to establish Portuguese dominance in the region, he dealt with anyone he viewed as competition – and those he didn’t – with ruthless violence. On one occasion he intercepted a ship in the Indian Ocean with 400 unarmed pilgrims on their way to Mecca.

After looting the boat and locking the men, women and children below deck, he set fire to the ship and burned them all alive. An eye witness described how da Gama was unmoved after looking through the porthole to see panic-stricken mothers holding up their babies and begging for mercy.

While the Portuguese were tentatively scoping their way along the coast of Africa looking for a way around to Asia, the Spanish were looking to the west. They had the same ambitions as the Portuguese – to tap into the spice trade, albeit from a different direction.

Christopher Columbus

Christopher Columbus, an Italian explorer, was the man hired by the Spanish monarchs to find the route.

Contrary to popular belief, Columbus and his contemporaries knew that the world was round, not flat, so to seek Asia travelling west across the Atlantic was not an unreasonable strategy.

What Columbus didn’t know about was the existence of the American continents. No one knew about them. So when Columbus sighted land during his first voyage in 1492 he assumed he had discovered the other side of Asia, which is how the Caribbean gained its misnomer of the West Indies.

The New World

The land Columbus found – he would return another three times in his lifetime – quickly became known as the New World, and word spread throughout Europe like wildfire.

Columbus never did make it to Asia and he wasn’t the first European to reach the Americas (as you may remember, a Viking expedition travelled there hundreds of years previous), but he was the first European to establish regular contact with the new lands, and for this he became one of the most important figures in the history of the world.

One obvious yet incredibly challenging journey that still had to be made was a full circumnavigation of the planet. This challenge was given to the Portuguese explorer Ferdinand Magellan, hired by Spain, who in 1519 set sail across the Atlantic with the same goal as Columbus: to find a westerly route to the Spice Islands, from which he could carry on in the same direction all the way back to Europe, thus completing a full loop.

Map of the Maluku Islands

The voyage was unsurprisingly tortuous, and by the time the fleet eventually found its way to the Pacific after crossing through the southern tip of South America — now known as the Straits of Magellan — there had been mutinies, storms and wrecks. Still, the remaining men pushed on across the Pacific and found their goal: the Spice Islands.

For Magellan, this was the region where his journey ended. He decided to try and convert the inhabitants of Mactan, an island in the Philippines, to Christianity, and when the leader of the island refused, Magellan returned with the intention to attack. The resulting battle didn’t go well for the captain: he was incapacitated by a bamboo spear and subsequently hacked to death by the locals.

Some of his men survived and carried on the journey, now under the leadership of a man called Juan Sebastian Elcano, and by 1522 arrived back in Spain. Of the five ships and 270 men that originally set sail three years before, one ship returned with just 18 survivors.

By the turn of the seventeenth century the coasts of most of the world’s significant landmasses had been mapped to varying degrees of accuracy, but there was one major omission: the 3 million square miles of land that we now know as Australia.

Medieval Europeans suspected the existence of a great continent, mainly based on the theory that a certain amount of land in the Southern Hemisphere was needed to balance out the land in the Northern Hemisphere. But no one had ever actually seen it.

Abel Tasman

Not until, that is, a Dutch navigator called Willem Janszoon landed on the north-eastern tip of the country while searching for trading posts in 1606.

He soon departed back to Asia, though, and another 40 years would pass before someone saw fit to delve a little deeper. That person was a Dutch explorer called Abel Tasman, who between 1642-44 became the first explorer to circumnavigate Australia.

Tasman also became the first explorer to reach Tasmania (his namesake), New Zealand and many of the Pacific Islands, including Fiji. He was sufficiently interested enough in Australia to afford it the name New Holland, loosely claiming it for the Dutch, but neither he nor any of his compatriots ever settled there.

Worlds Collide

The Columbian Exchange

The Age of Discovery began with Portugal trying to tap into the lucrative spice trade and ended with a global mingling of cultures, foods and technologies on a scale never seen before. Historians have termed this meeting of the Old and New Worlds the Columbian Exchange, after the explorer who was the first to establish regular contact.

The extent to which people benefited from the Columbian Exchange really depended on where they were born. Generally speaking, the march towards globalisation was enormously advantageous to European powers and mostly cataclysmic for everyone else.

Native American Indian Tribe

Diseases like small pox and measles had always been a problem for Europeans and Asians, but after countless generations many had developed a natural immunity. Native Americans, however, had no immunity whatsoever, and these diseases absolutely decimated their populations. Conservative estimates claim that 85-95% of these peoples had been wiped out by Old World diseases within 150 years.

This meant there was practically no resistance to European powers seeking to establish colonies in the Americas. When these colonies had been established, people were needed to work in the fields of the new lands, and for this resource Europeans turned their attention to Africa. And so began the Atlantic slave trade.

One of the many, many consequences of the Age of Discovery and Columbian Exchange was that Europe became phenomenally rich – and remains so to this day.

Antiquity Revived

The Renaissance Blooms

As we learnt earlier, after the collapse of the Roman Empire, Europe was plunged into what historians have termed the Dark Ages, one of the many lowlights of which was the Black Death, which wiped out half the continent's population.

Perhaps understandably, by the time European powers had finally gathered themselves and achieved some stability they began looking back to the ancient civilisations of Rome and Greece with an air of nostalgia.

View of Florence from the Piazza Michelangelo

The renewed interest in classical civilisations – combined with a surplus of wealth – sparked a cultural movement called the Renaissance. It sprouted in Florence before blossoming throughout Italy and then the whole of Europe, and at its essence was a revival of European art and literature inspired by classical models.

It was this cultural movement that set the scene for the first ever gap years.

Lads on Tour

The Birth of the Gap Year

Starting in the mid 17th century, young male English aristocrats began travelling across the Channel to explore France, Italy and other countries on the continent. Money was no object and they would hire guides and carriages as and when they needed them.

The aim was to build on their classical education, to see the architectural skeletons of the Ancient Greek and Roman worlds with their own eyes, to mingle with the high society of their European neighbours, to study first-hand the grand masterpieces being created by men like Leonardo da Vinci and Michelangelo, to perfect their foreign languages and etiquette, to commission paintings and sculptures which they could bring home as souvenirs – proof of their broadened horizons and connections.

These men became known as the Grand Tourists and their journey was called the Grand Tour. The itinerary depended on the whims of individual travellers but the compulsory destinations were Paris, Florence and Rome, where anything up to a year would be spent in each.

Industry Arrives

And the Railroad Sparks Mass Movement

The Industrial Revolution began in Britain in the mid 18th century and spread throughout Europe and North America over the next few decades.

The ways in which it changed society are practically infinite but as far as our story is concerned one of the most interesting developments was that of the railroad.

Train in Temecula, 1888

The main cities of Europe were already reasonably well-connected by actual roads, but railways offered a considerably cheaper, quicker, safer and more comfortable alternative.

Britain was the first to recognise the infrastructural advantages of railways and by 1850 – just 20 years after the first intercity track opened – there were an astonishing 7,000 miles of railroads stitching the country together.

Brits Abroad

Leisure Travel Launches

One summer’s day in 1841 a man called Thomas Cook was walking to a meeting in Leicester, England. The meeting was hosted by his local temperance society, part of a wider movement which campaigned for moderation of alcohol intake. Members believed alcohol abuse was the root cause of most of the social problems in Victorian Britain.

Cook later recalled from that walk: “The thought suddenly flashed across my mind as to the practicability of employing the great powers of railways and locomotion for the furtherance of this social reform.”

Upon reaching his meeting, Cook suggested to the members that for their next get-together, which was 12 miles away in the town of Loughborough, he charter a train to get them there and back, and provide everyone’s lunch, too. The idea was met with great approval, so Cook negotiated a deal with Midland Counties Railway Company. Each passenger would be charged a shilling for return tickets and food, and Cook would receive a percentage of the total figure made.

Portrait of Thomas Cook

Thomas Cook head offices at Ludgate Circus, London

1888 Thomas Cook Handbook

The concept was simple. Everyone was a winner. The railway company was happy to get so many seats filled up in one booking.

Thomas Cook was happy because for arranging the excursion he received a share of the profits. And the passengers were happy because they didn’t have to go to the bother of organising their journeys. Or lunch. Everything was taken care of in one handy package.

Cook could never have known it, but the thought that flashed across his mind on that summer’s day in 1841 planted the seed for what is today the world’s fastest growing industry, one which sees more than a billion people cross international borders every year, and one which is worth more than a trillion dollars to the global economy: tourism.

Buoyed by the success of that initial outing, Cook continued for the next few years to organise similar excursions, in the process inadvertently becoming the world’s first travel agent. It wasn’t long before he saw the potential for leisure travel and started putting together tours of Scotland, and then eventually overseas trips to Europe, Egypt and the States.

Thomas Cook coach

Thomas Cook tour party

Unlike the Grand Tours of the 17th and 18th centuries, these trips were available to a much wider range of people, namely the newly created middle classes.

Thomas Cook died in 1892 and his sons and grandsons continued to run the family business, which by the turn of the twentieth century had offices in Australia and New Zealand and had organised over 3 million trips.

And that was just the beginning.

Titanic Ships

Steaming the Seas

Transport to travel is what armies are to conquest: the better the former the easier the latter.

The introduction of railways marked an enormous leap forward in facilitating mass transit but it wasn't the only invention to emerge from the fires of the Industrial Revolution.

Hot on the heels of the new locomotives were enormous ships capable of carrying people en masse across oceans in relative comfort for the first time in history. Unlike their predecessors these ships were made from steel, not wood, and powered by steam, not wind.

The American-built SS Savannah is often cited as the first steamship to make a transatlantic crossing, from Georgia to Liverpool in 1819, but this is a slightly misleading accolade. The ship was a hybrid of a sailing ship and steamship, and it only actually used steam propulsion for a tiny portion of the trip. Furthermore, during the historic crossing, the ship was completely devoid of passengers: so novel was the new design that people simply mistrusted it and not a single ticket was sold.

Interior view of a steamship

Still, the scene was set and with constantly improving technology it would only be a matter of time before steam-powered engines replaced sails universally.

The most important thing was that a regularly scheduled transatlantic crossing was fast becoming a reality; the Old and New Worlds were being connected on a scale that just a century earlier would have been unimaginable.

One of the most famous – or infamous – ships of this age was the aptly named RMS Titanic, the colossal passenger liner which struck an iceberg in the North Atlantic in 1912 on her maiden voyage to America, and crashed onto the ocean floor soon after. More than two thirds of the 2,224 souls on board perished in the freezing waters.

The Titanic, like many of the great ships of the time, was more than just a vessel: it symbolised a new life in a new world. The late 19th and early 20th centuries saw millions of people from Europe emigrate to the United States – the New World – in search of a better life, something that became known as the American Dream.

Pushing the Boundaries

There are many limits within our world, but one thing which knows no bounds is our collective curiosity.

Our destiny as a race is to explore, to travel, to turn over every rock in our universe. The great voyages of the Age of Discovery marked a golden age for travel, and inspired the confidence needed to keep going.

The world had begun to take shape on our maps and in our minds, but enormous blank spaces remained. Victorian explorers like David Livingstone and Henry Morton Stanley delved into the wild, uncharted heart of the African continent, while explorers like Robert Burke and William Wills traipsed across the burnt, bewildering vastness of the Australian Outback.

Portrait of David Livingstone

Portrait of William Wills

Portrait of Charles Darwin

In 1831 a young naturalist called Charles Darwin set off on a five year circumnavigation of the planet, during which time he would become entranced by the world’s geology and biology, and many years later reveal his theory of evolution by natural selection.

The last century has seen the world’s attention drawn towards the extremities of the planet; the deepest oceans, the highest mountains, the bitter polar regions. And eventually beyond our watery little world, into Space itself.

The conditions at the top of Everest, the highest mountain in the world, read like a weather forecast from an alien planet: 200mph winds, brutally cold temperatures, a disquieting deficiency of breathable oxygen.

In 1953 Edmund Hillary became the first man to summit the peak, along with Nepalese Sherpa Tenzing Norgay.

Unlike many of the great explorers discussed in this history of travel, Hillary wasn’t in search of trading routes, religious sites, a new place to live, fame and fortune, conquest or science; he simply climbed it because it was there. Which is as good a reason as any.

Mount Everest

Edmund Hillary and Tenzing Norgay

He would later say: “If someone starts out on a challenging activity, completely confident they’re going to succeed, why bother starting? It’s not much of a challenge.”

Hillary certainly had no guarantees of success, and few could deny the enormity of his challenge. Although his climbing gear was clearly adequate for him, it was thoroughly rudimentary compared to today’s standard of equipment. Even now, for every 10 people who successfully summit Everest, one person dies.

What makes Everest so incredibly dangerous is not so much the mountain itself – technically speaking, the terrain is fairly straightforward for experienced mountaineers – rather the extreme conditions in which its peak resides.

The portion of the mountain which is over 8,000 metres high is known as the Death Zone, due to the extreme temperatures and lack of breathable oxygen. This is so debilitating on the human body that the final mile to the summit usually takes climbers – typically people at the very peak of physical fitness – anything up to 12 hours to trudge. Frozen corpses are an eerily common sight in the Death Zone of Mount Everest.

The deepest ocean on our planet is the Pacific, and the deepest part of the deepest ocean is the Mariana Trench, the floor of which sits almost seven miles beneath the surface. For context, that’s about the same distance a commercial airliner at maximum cruising altitude flies from the ground. More than 6,500 ft higher than Mount Everest.

The first people to fully descend into the abyss – all 35,797 ft of it – were Jacques Piccard and Don Walsh on 23 January, 1960. Piccard was a Swiss oceanographer and engineer, and Walsh was a US Navy Lieutenant.

Jacques Piccard and Don Walsh in their submersible

The bravery of Piccard and Walsh can scarcely be emphasised enough. The deepest point of the deepest ocean is – as far as humans are concerned – one of the most inhospitable places on our planet.

The weight of the water at that depth is scarcely comprehendible: for every square inch there are eight tons of pressure. If their submarine – it was called the Trieste – were to succumb to the immense forces bearing down upon it, the result would have been catastrophic.

At the 30,000 feet mark, one of the outer window panes on the vessel cracked, causing the vessel to shudder violently. This meant there was just a single pane of glass between the men and instant death thought, unaware of the damage, they decided to press on and continue their descent regardless.

Almost five hours after beginning their journey, Piccard and Walsh touched down on the primordial ooze that covers the floor of the Mariana Trench. Once there, they discovered the crack in the outer window pane, which meant they only spent 20 minutes at the bottom before heading back up.

Amazingly, before this feat, not even an unmanned vessel had reached the bottom of the Mariana Trench. When asked many years later why he didn’t just send a robot down there, Don Walsh said: “You gotta be there because that’s what we do.”