Look at a map of Asia and you can't help but be intrigued by the vast, seemingly vacant expanse at its centre. But while the mountains of Tibet, the deserts of Xinjiang and the rolling steppes of Kazakhstan might not have many roads, or massive towns, they are far from empty. Home to ancient and fascinating cultures (including the brutally oppressed Uighur and Tibetan minorities in modern-day China) these lands once sat at the heart of the network of trade routes known as the Silk Roads. Travelling through them now might feel like you're in the middle of nowhere, but these places were once considered the centre of the world.
"Travelling here now might feel like you're in the middle of nowhere - but these places were once the centre of the world"
Recently British photographer Marc Sethi embarked on an epic journey from Beijing to Moscow, travelling through Tibet, Xinjiang, Kazakhstan and Russia. Accompanied for large sections of the journey by writer Monisha Rajesh (author of Around the World in 80 Trains) Sethi shot extensively wherever he could. Here are a selection of his finest photos from the trip - providing an incredible snapshot of this little-known region.
1) At a secluded Buddhist temple on the outskirts of Lhasa, a Tibetan woman protects her face from the heat of thousands of candles as she wanders round and round the room keeping them all alight.
2) The wizened heads of the Tian Shan mountain range nudge the underbelly of gathering storm clouds as the train from Urumqi in Xinjiang Province crosses over the border from China into Kazakhstan. As seen through the window of the last carriage.
3) A single plastic flower sits in a vase on the table in an empty compartment on the Qinghai-Tibet railway to Lhasa.
4) A regular feature of the landscape on the train's ascent to Lhasa are strings of traditional Tibetan prayer flags, their multi-coloured triangles flapping in the wind and decorating the outside of nomadic tents.
5) Just before 5AM, the train from Urumqi pulls into Almaty station and passengers disembark and vanish in a matter of minutes, leaving the platform in eery darkness and desolation.
6) 1476 Smiling, a Uighur chef stacks washed dishes in his kitchen after a long afternoon serving fried mutton noodles and steamed mutton and onion dumplings to local people at a covered market in Turfan, Xinjiang Province. The Chinese government's cultural genocide of Muslim Uighurs is already evident from the chef's lack of beard which are no longer allowed for Muslim men.
7) Elderly Uighur men perch on benches in Turfan, Xinjiang Province. A common sight, they drink tea, eat fresh kebabs grilled on the street and catch up on the day's affairs.
8) A Uighur man dines on fat noodles fried with mutton, tomatoes and cumin unique to the area, as another checks his teeth in the mirror. Uighurs and Han Chinese remain entirely segregated, eating, drinking and socialising within the confines of their own communities.
9) In the early evening women gather at a hairdressing salon in Turfan sporting a weird and wonderful range of styles.
10) A Kazakh train guard waits on the platform of Almaty station in the midday sun.
11) The 55-hour train journey from Kazakhstan's capital, Astana, to Moscow is a long and tortuous one. After a good meal, the best way to kill time is to doze in the cosy but often over-heated compartments.
12) On the train from Astana to Moscow, passengers can catch glimpses of farming communities, their ramshackle sheds filled with logs and old machinery, their perkily painted houses fitted with satellite dishes.
13) A hopeful fisherman parks his bike against a wall and waits on a bridge by the moat surrounding the walls of the Forbidden City in Beijing, China.
15) The Badaling section of the Great Wall of China curves along the crest of the hill like a dragon's tail. Late evening visitors climb the steep slabs before taking a cable car back to base.
16) China's so-called "Ghost Cities" are a strange but common feature of the country's landscape. Popping up in clusters every few miles, these empty-looking hubs are built to encourage urban Chinese to spread out into lesser-populated areas, though many remain completely uninhabited and draped in tarpaulin.
17) A husband and wife relax in the soft-sleeper compartments on the night train, which feature coat-hangers, soft duvets, plastic flowers and gold curtains hanging in the windows - a far cry from the hard-sleeper dormitory-style coaches at the other end of the train.
18) A grandmother and her grandson return from breakfast on the sleeper train from Shanghai to Xining where passengers can find bowls of cold congee and dried pickles, along with hot jasmine tea.
19) Xinjiang Province is home to some of the most spectacular mosques. This one sits in a valley in the middle of the Taklamakan desert.
20) Sugar-coated mountains slope in the distance of the Qinghai plateau where raggedy-looking yaks graze on mottled tufts of grass and Chinese trucks rumble alongside the train.
21) Lhasa: A Chinese motorcyclist promoting the Chinese Premier Xi Jinping, rides past the Potala Palace, the former home of the exiled Dalai Lama. The palace is now a place of pilgrimage to Tibetans of all ages who travel miles to prostrate themselves on the pavement outside the palace.
22) After the Chinese invasion and the Cultural Revolution, almost all Tibetan monasteries were brought to rubble, the land used for property development. The Sera monastery is one of the few remaining in Lhasa, a quiet and brightly coloured spot that looks fabulous in the Tibetan light.
23) Butchers in the main marketplace in Lhasa carve up their hunks of yak meat, often leaving the heads at the foot of the stall. Largely used for momos and curry, the meat is fatty but full of flavour.
24) A family of Tibetan nomads sit down to snack on bananas after visiting the Potala Palace on pilgrimage. Ruddy-cheeked with high, chiselled cheekbones, their features make them instantly identifiable among the influx of Han Chinese to the region.
25) Pilgrims prepare to prostrate themselves outside the walls of the Potala Palace in Lhasa where the ancient and modern go hand in hand. An elderly nomad to the left of the frame carries a traditional mani wheel, shaking it methodically as she walks around in a pair of Nike trainers.
26) Identifiable by their burgundy robes, two young monks smile in front of the Potala Palace in Lhasa. Although a "patriotic education programme" has been put into place by the Chinese, forcing Tibetans to publicly denounce the Dalai Lama, most Tibetans revere their leader in secret with many young men still training as monks from a young age.
27) Carrying a prayer necklace, an elderly Tibetan crosses a road in central Lhasa behind a convoy of armed Chinese military who patrol the streets with firearms, set up blockades on the main square, and force nomads to go through scanners at the entrances to temples – all under the guise of protection for Tibetans.
28) The morning market sees a roaring trade in caterpillar fungus to buyers from Guangzhou. Known as yartsa gunbu, the caterpillars are believed to alleviate all kinds of ailments ranging from heart disease and asthma to HIV. A pound of the top-quality grubs can sell for around £30,000. Post market the buyers sit around in the sun and relax, pleased with the success of the morning's sales.
29) The main square opposite the Potala Palace features a giant billboard of the Chinese Premier, Xi Jinping, along with a number of other propaganda posters declaring the benevolence of the Chinese to the Tibetan people.
30) On the main road a tacky propaganda poster reads: “ Welcome to prosperous, harmonious, legal, civilized and beautiful socialist new Tibet.” One of the much more blatant attempts to breeze over the hostile takeover by Han Chinese.
32) A Tibetan nomad and her daughter peer with curiosity into a shop in central Lhasa selling skin-whitening cream, a product widely used by Han Chinese.
Marc Sethi is a photographer based in London. You can see more of his work on Instagram.
Monisha Rajesh is the author of Around the World in 80 Trains, which is out now.