Barely 100 years ago, Shackleton made his epic voyage to Antarctica.
Only a decade before, the Wright brothers had taken powered flight from theory to fact in the same year that the Younghusband Expedition had penetrated to the inner core of Tibet. In the process, they and their like blazed trails that became the classic journeys and we follow in their footsteps.
Today you can see Adelie penguins on the coast of Antarctica and come back to a spa treatment aboard your vessel. Lhasa is a train ride from Beijing.
The trip along the Nile, the rail journey from Cuzco to Machu Picchu, the Buddhist Himalayan hermit kingdoms - journeys that were once at the forefront of exploration can now be done with a well-chilled chablis over dinner and a scented towel delivered by your room butler.
Yet the age of discovery is far from over. "We just might be entering the most amazing era of exploration ever," according to Sven-Olof Lindblad of Lindblad Expeditions.
So what are the classics to come, the journeys that are just beyond the horizon of our radar, the ones that will surprise, delight, reveal wonders unplumbed and open new doors of perception?
Ever since Marco Polo, the Silk Road has been a name to conjure dreams. Intrepid Travel is one of several adventure tour operators offering the Beijing to Tashkent overland trip, with the option to continue to Moscow.
"It's my favourite journey, an absolute epic," says Tara Kennaway, Intrepid's assistant product manager for Asia. "The exotic mix of cultures and history and landscapes - they make for a magical experience."
World Expeditions has come up with a new take, a 21-day trip from Tashkent to Tehran. "It's a game-changer," says Sue Badyari, the chief executive of World Expeditions.
"That mystique of Iran is what puts the finish on this version of the Silk Road. You've got big deserts and caravanserais used by travellers on the route between China and the West, and cities that date back to the earliest days of civilisation."
With Myanmar out of the deep freeze, the Burma Road is another potent name teetering on the cusp of fame.
Running from Lashio in northern Myanmar to Kunming in China's Yunnan, this 1100-kilometre road was wrestled through monsoonal rainforest by 200,000 Chinese and Burmese labouring over steep terrain in the 1930s. "It's an amazing part of the world, raw and very untouristed," says Ian Marsh, director of Brisbane-based adventure operator Global Drift.
"Along the border you've got hill tribes that have had very little contact with Westerners, and the mountainous region of Yunnan is a rich tapestry of minorities and Khampa people from western Tibet."
Global Drift has operated Burma Road trips in the past "although it's an on-again, off-again proposition". "The road north from Lashio sometimes gets closed off by the Burmese," Marsh says.
Having a jet aircraft on call enables you to pack a major-league list of sights into a tight framework and delivers you right to the sweet spot. One day you're seeing the Taj Mahal by moonlight, the next you're walking in Jordan's biblical landscapes. The aircruising experience comes with five-star food and lodgings, rekindling the days of the Catalina flying boat service between Australia and England when the aircraft would fly by day, splash down in the evening and boatmen would pole you off to a posh hotel.
Setting the pace is Captain's Choice. New for this year is The Magic of South America. "Having your own plane in a place like South America makes a huge difference," Captain's Choice managing director Phil Asker says.
"For example, when we visit Iguacu Falls, we fly in from Buenos Aires in the morning, lunch on the plane and spend six hours at the falls, dinner back on the plane going into Rio and after that we head off to Havana."
Safari specialist Abercrombie & Kent combines its African expertise with a charter jet aircraft. Its first Africa aircruise - Across a Continent by Private Jet, in 2014 - knits together the rock-carved churches of Lalibela in Ethiopia, the mountain gorillas of Uganda, Botswana, Namibia, Victoria Falls and South Africa.
Conveyance is aboard a chartered Boeing 737 with room for just 40.
According to Sujata Raman, the managing director at A&K's Melbourne office, the trip sold out in just a few weeks, despite the $80,000 price tag, and a second is now scheduled.
In 2014, A&K lifts the bar on the airtour concept with a round-the-world trip that stitches together nine countries in 26 days, with just 49 fellow passengers aboard a Boeing 757-200ER in an all-business-class configuration.
One of the trailblazers of aircruising in Australia, Bill Peach Journeys, is spreading its wings with a 17-day aircruise from Sydney to London, which puts 30 guests aboard an Embraer aircraft and has Angkor, the hill-tribe country of northern Thailand, the Taj Mahal, the souk in Muscat, the Nile and Santorini on its itinerary.
Small ships can go where nothing else will, from the wilder shores of Papua New Guinea to Greenland'
s ice. The president of Lindblad Expeditions, Sven-Olaf Lindblad, is a leading exponent of expeditionary cruising. "The Northwest Passage," is his unhesitating answer when I ask him what's the next frontier. "It's hugely exciting, but it's become a possibility for all the wrong reasons."
Global warming and rising sea temperatures have created an ice-free sea route through the Arctic Ocean across the top of North America over recent northern summers.
In 2014, a Lindblad Expeditions vessel will make a 25-day voyage between Iceland and Kugluktuk, the Inuit community close to the Alaska-Canada border, with fiords, massive ice, polar bears, whales and seals on the to-see list.
Another frontier that Lindblad Expeditions is probing is Peru's Pacaya-Samiria Reserve, part of the upper Amazon River and known as "the jungle of the mirrors" for its still waters that reflect the surrounding rainforest, an ecological treasure chest.
Although the riverboat journey along the Irrawaddy from Mandalay is as old as Kipling, the thaw in Myanmar's relations with the wider world gives it new prominence.
"This has gone berserk," according to Phil Asker of Captain's Choice. "We recently did a trip downstream from Mandalay to Rangoon, past little villages all the way, and it still feels very natural, virtually untouched by tourism."
The luxury option on the Irrawaddy is The Road to Mandalay, operated by Orient-Express hotels, which this month launches a new luxury cruiser, the Orcaella. The retro-style Pandaw vessels, however, look more the part, and offer a wider repertoire of river cruises.
With a road imperilling the integrity of Nepal's Annapurna Circuit, adventurous trekkers are turning their heads east to Manaslu. Snaking through remote villages and terraced fields that spill down from some of the world's highest peaks, the 20-day Manaslu Circuit follows the valley of the Buri Gandaki River through Tibetan villages and finally into an amphitheatre of snow-covered peaks. "It's a sensational walk, comparable to the Annapurna Circuit in terms of length and rigour," according to Sue Badyari of World Expeditions.
"[It's] ideal for anyone who wants to experience the wild side of Himalayan trekking."
The Camino de Santiago pilgrimage trail finds a quieter echo in the East. One of the most compelling of Japan's pilgrim routes follows the diarised journey of the revered haiku poet, Matsuo Basho.
"He kept a very beautiful journal of his travels, The Narrow Road to a Far Province," says Ian Perlman, an architect, walker, writer and long-term resident of Japan. "Even following in his footsteps almost four centuries later, in the age of bullet trains, you get quite a sense of it, especially among the pagodas and forest shrines of northern Honshu."
For pilgrims with more ascetic tastes, the 1000-year-old Kumano Kodo threads through forests and villages on the Kii Peninsula, south of Osaka. "It's in a mountain eyrie," Perlman says, "much of it through wild country, but there are enough clues to make it work as a pilgrimage trail. It's a syncretic mix of Buddhism and Shinto layered with history and poetry, although very few foreigners walk the full Kumano. It's also very austere if you do it seriously. You have to fast and purify yourself under waterfalls, and women are excluded from certain parts."
Erupting from the arid plateau of south-western Tibet, the blunt thumb of Mount Kailash, the Snow Jewel, is a sacred pilgrimage site for both Buddhists and Hindus and an emergent pilgrimage for intrepid Westerners, especially around the time of the April-May Saga Dawa Festival.
The object of the pilgrimage is to wash away all negative karma by walking the kora, the 50-kilometre circuit of the mountain's base. Westerners who come witness one of the great tantric festivals and experience a high-altitude, breath-sapping walk that focuses the mind.
The great era of building railways may be over, but there are still frontiers to be crossed. In the world of high-speed train travel, China is making the running.
Scheduled for completion at the end of 2014, the 1776-kilometre Lanzhou-Urumqi high-speed railway will be the world's longest such train service. With onward connections to Beijing, the 3450-kilometre journey right across China from Urumqi to the capital will take less than 12 hours, travelling at a maximum speed of 350km/h.
Running on the other rail from high-speed train travel is nostalgia. Launched in 2007, the ultra-luxury Golden Eagle introduced the Louis Vuitton traveller to the Trans-Siberian journey between Moscow and Beijing or Vladivostok.
"It's a very different clientele from those who used to travel on the Trans-Siberian, and it's really caught the imaginations of Australians," says David Stafford, the chief executive of Rail Plus.
Ecuador has reopened the line between Quito and the coast, one of the world's most spectacular railway journeys. Closed after landslides in the 1990s, the four-day trip aboard a luxury train operated by Tren Crucero takes in the Valley of the Volcanoes, with nights in hotels.
In Japan, the Seven Stars in Kyushu luxury sleeper train is scheduled to begin operating in October this year, calling at the island's select tourist destinations on a three-night itinerary.
In Africa, luxury train operator Rovos Rail rekindles the British imperial dream of a Cape to Cairo journey. Billed as "the ultimate African experience", the 28-day trip early in 2014 visits Botswana, Victoria Falls, Ngorongoro Crater, Zanzibar, Khartoum and the Nile, although only the southern part of the journey is by rail.
The final frontier, so we're told, and the sub-orbital space flights promised by Virgin Galactic are filling fast. Virgin boss Sir Richard Branson recently anointed December 2013 as the launch date for paying passengers keen to bravely go where few have gone before. Six passengers at a time will travel aboard SpaceShipTwo, which will piggyback on the twin-fuselage launch aircraft, WhiteKnightTwo, to an altitude of 15,000 metres, where it will separate and increase speed to 4000km/h.
At 100 kilometres above the Earth's surface, in inky darkness, the rocket will switch off its motor and passengers will experience about six minutes of complete weightlessness in zero gravity as the rocket ship travels in a parabolic arc, at a cost of about $700 for every second of float time.
Several hundred wealthy and notable names have signed up for the experience, including Arnold Schwarzenegger, Stephen Hawking, Paris Hilton, Justin Bieber and Brad Pitt and Angelina Jolie, although prudently not on the same flight.
SIX OF THE ALL-TIME CLASSIC JOURNEYS
Celebrated in song and folklore, this highway between Chicago and Los Angeles became emblematic for Depression-era refugees heading west and a disaffected postwar generation for whom it became life in a footloose chapter of the American Dream.
The original passenger service between Paris and Istanbul began in 1883. Today it exists only in truncated form, a five-night luxury train trip between London and Venice, and is more about dressing up than discovery.
THE NILE RIVER JOURNEY
Luxor to Aswan along the Nile River is a slow-motion journey through history, with 3000-year-old temples and pharaonic tombs as punctuation marks.
The classic long-distance Himalayan circuit trek now debased by the construction of a road up the Kali Gandaki, the world's deepest gorge, to link Pokhara with the Tibetan border.
EL CAMINO DE COMPOSTELA
The Way of St James, the long-distance walking trail from France across the Pyrenees and to the Spanish city where the body of St James is supposedly interred, is the classic modern-day pilgrimage trail for Christians.
The best known of all New Zealand's walking trails, this 54 kilometre, four-day dazzler climbs through beech forests and across the Mackinnon Pass, with a slight detour to 580-metre Sutherland Falls before it ends at Sandfly Point, on the shores of Milford Sound.
- Sydney Morning Herald