I plunged my arm down into the icy water. "Muy grande," said Raul, the 4x4 driver, describing the size of what I would find down in the hole. I searched around with my hand until I found a large cluster of crystals hanging on an underwater shelf, then broke it off and pulled it out. "Bonito!" said Raul.
It really was beautiful: a fist-sized collection of sparkling white crystallised salt, perfectly formed cubes that looked smooth and man-made, more like a small modern abstract sculpture than a work of nature. They're quite common beneath the surface of Bolivia's salt flats, found in holes known as "salt eyes" formed when the salt expands and contracts with daily changes in temperature. I asked if the authorities minded people taking souvenirs. "No one minds at all," said Javier, my guide. "There are 10 billion tons of salt in the Salar de Uyuni. No one will miss it."
Bolivia's Salar de Uyuni, the world's largest salt flat, is a unique area: strange, beautiful and immense; a brilliant white landscape that is half the size of Wales. Until recently, it was also difficult and time consuming to get to, requiring either the use of a private vehicle for the eight-hour drive from the tourist hub of La Paz, or a combination of bus and train taking more than 12 hours. Now it's possible to fly to Uyuni from La Paz in one hour. But despite the country's President Evo Morales inaugurating Uyuni's new airport in July this year, many local and international operators aren't aware that the new flight is available.
I looked out of the window of the compact 18-seater plane as we arrived over Uyuni. Beyond the city limits, I could see the shift from scrubland to the bright white where the salar, the salt flats, began. They continued beyond the horizon.
"The thing about Uyuni," said Javier, who met me at the airport with driver Raul, "is that there's no place like it in the world." At 3,656m the air is as pure as the perfect white landscape. There's a popular local story that after a new cemetery was built in Uyuni, not one of the town's inhabitants of 15,000 died for a whole year, because the dry cold air makes it hard for contagious diseases to spread. Eventually, according to the tale, the town had to "borrow" a corpse from nearby Pulacayo to break ground at the cemetery.
The dazzling landscape does come with a health warning, though. "I advise from now on you wear your sunglasses," said Javier as our 4x4 reached the shores of the salar. People have been known to experience headaches, sun blindness and other problems due to the brightness.
Raul drove past men with shovels loading piles of salt into trucks. There are no roads across the salt, just faint tracks from other tourist vehicles. Local drivers navigate using markers such as the Tunupa volcano and other surrounding peaks. "If the driver isn't from these parts, it's very easy to get lost," said Javier.
We travelled to the popular island of Incahuasi and walked around the cacti-covered dot of land to the shrine to Pacha Mama (Earth Mother) at the summit. Fish Island, a quick drive across the salt, was entirely tourist-free. I climbed fossilised coral cliffs to look over the vast landscape. I held still: absolute silence.
A lone vicuña (like a small llama) ran alongside us as we arrived at the village of Jirira. Large tents set up on the shore were to be our home for the night. It was a memorable spot to camp, with the salt flats directly ahead, llamas wandering on the slopes, flamingos grazing on the beach and the ragged crater of dormant Tunupa behind us.
After a sunset that turned the sky pink and mauve, we settled in. This is a harsh high-altitude environment, intensely cold at night, but the tents were up to the task. Not only did we eat several dinner courses at proper tables and chairs in the kitchen tent, but then someone announced the excellent idea of hooking up electric blankets to a generator. After checking out the brilliantly clear night sky, the electric blankets, combined with thick layers of duvets, thermals and five layers of clothing, ensured a comfortable night's sleep.
The standard way to explore here is on a 4x4 tour, but I had something more exciting lined up. I met Robin, a Dagenham-born Bolivian, in Uyuni who kitted me out to ride a 650cc motorbike (a yellow and black Suzuki DR650) across the salar. As well as helmet, boots and jacket, sunglasses were again vital.
The feeling as the great bright white and blue of the salar opened out in front of us was extraordinary. Shallow surface water close to the shore perfectly mirrored the sky, as the bike purred along. Because the landscape looked like ice and snow, it took a while to accept the bike wasn't going to slip and slide. In fact, the salt terrain is quite grippy: hard and solid, like concrete.
We zig-zagged across the open plains, throttle open, with no other vehicles in sight. Even through sunglasses, the colours were vivid, the white and blue landscape so crisp and fresh it felt like we were riding through a toothpaste advert. The ground ahead sparkled in the sun.
"Here, you get the experience of the vast openness," said Robin over lunch on Incahuasi island, about an hour from the Chilean border. "It's easy riding but spectacular riding."
Robin and I gave each other lots of space in the afternoon. At times, he was just a black speck on the horizon; other times, we looped around and crossed each other's tracks.
Later, we left the salt and rode a sandy road along the shore to the "train cemetery" outside Uyuni, arriving as the sun was setting behind silhouettes of hulking engines and carriages abandoned to rust and graffiti after the collapse of the mining industry here in the 1940s. According to Robin, this area was the birthplace of football in South America. British engineers came here in the late 1800s to help build Bolivia's trains and railways, bringing the game with them.
I stayed overnight in the Luna Salada Hotel on a hilltop close to the flats. The hotel is made entirely from salt but, like the tents, is not without creature comforts – including gas fires to combat the chill. The walls are made from big bricks of salt with creamy white layers and brown mud layers, like big portions of tiramisu. The beds, chairs, tables and other furniture are carved from salt, the floors are a gravelly sodium chloride. The view contains salt, too: from the dining hall window, I looked out over llama-covered slopes leading down to the salar which stretched out to the horizon. To the north lay the dramatic crater of Tunupa.
The next morning, I drove north-east, stopping at the abandoned mining town of Pulacayo to see the last train robbed by Butch Cassidy and the Sundance Kid before the Bolivian army tracked them down and killed them. Beyond it, via some grand mountain scenery, was Potosí, the highest city in the world, where I stayed overnight. The city has a tragic past. It is known as Cerro Rico ("Rich Hill") for its large deposits of silver and other valuable metals. An estimated nine million workers died during the intense mining projects of the Spanish colonisers.
Sucre, just a few hours drive away, is the opposite of Potosí's narrow, occasionally gloomy streets. Here, everything is wide open and airy; the buildings stand bright and shining. Though La Paz is home to the government, Sucre remains the official capital of Bolivia. "There's still anger," Pedro, my local guide, told me as we sat on the central Plaza 25 de Mayo. "The people in Sucre say all the time this is the capital." Although Sucre lost the administration in 1899, there were violent protests to bring back the government as recently as 2007.
Otherwise, this is the most peaceful city in Bolivia, a Unesco World Heritage site of white colonial buildings. The Declaration of Independence was signed here back in 1825, and I visited Liberty House on the plaza to see a copy of it (the original is held in a local bank's vault).
Then I explored Sucre on foot. One of the capital's former names was La Ciudad Blanca (White City). Every building in the centre continues to be white-washed each year by government decree. I walked up to San Felipe de Neri Convent for the peaceful rooftop viewpoint and from there looked out over terracotta roofs and a sea of gleaming white houses, shops, museums, cathedrals and towers – the dazzling sunlight bouncing in all directions off shining surfaces. Here, as on the salt flats, sunglasses are less a fashion item than a piece of safety equipment. In this part of the world, it's hard not to be dazzled.
Area: 53 times the size of Wales
Year of independence: 1825
National animal: Llama
Opening lines of national anthem: Bolivianos el hado propicio coronó nuestros votos y anhelo (Bolivians, a most favorable destiny has at long last crowned our vows and longings)
Travel essentials: Bolivia
* The writer travelled with Rainbow Tours Latin America (020-7666 1260; rainbowtours.co.uk), which offers a 10-night package including La Paz, Salar de Uyuni and Sucre from £2,495 per person. The price includes flights from Heathrow to La Paz, one night's luxury camping with breakfast, one night's B&B at the Luna Salada salt hotel and B&B accommodation throughout, plus all land transfers.
* British Airways/American Airlines (0844 493 0787, ba.com) fly from Heathrow to La Paz via Miami with returns starting at £930.
* Amaszonas (00 591 2 222 0848; amaszonas.com) operates flights from La Paz to Uyuni four times a week.
* Motorcycle Tours Bolivia (00 591 787 73787; motorcycletoursbolivia.com) offers one-day motorbiking trips on the Salar de Uyuni from £150 per person.