Feeling low on energy? Have a bath in a barrel of crude oil

Wrapped in a white bathrobe, Arkady Shabunin stares out the window of the Naftalan clinic at the carcass of a yellow Lada balanced on four piles of bricks. It is an unlikely place for a spa retreat but the captain of a Siberian rafting team has travelled 1,800 miles to the Azeri capital of Baku for 10 days of massages and baths – using not mud, nor seaweed, but crude oil.

The attendant beckons. Mr Shabunin strips and enters a ceramic-tiled room. He grabs hold of the ornate bath handle and lowers his body into 35 gallons of black gold – as much as a barrel. Orangey filaments swirl about on the surface, sticking to the enamel and to the hair on his skin. The smell from the 40°C bath makes our heads spin.

If you strain your eyes, you can just about make out the tankers plying the Caspian Sea, transporting the light crude that Azerbaijan exports to the world. But the oil used here gushes out of the Earth at Naftalan, a small town 160 miles north-west of the capital.

"Naftalan is too heavy for the industry," Dr Alif Zulfugar, the manager of this unlikely spa, explains. "It is used only for healing purposes. It doesn't get treated in any way. It passes directly from the source to our tankers and then into our basins." Clients flock to the clinic from all over the former Soviet states, and increasingly from the Emirates and even Europe.

Marco Polo mentioned the virtues of Azeri oil in the 13th century. In The Travels, he wrote of a "fountain from which oil springs in great abundance ... not edible but good for burning and to treat men and animals with mange, and camels with hives and ulcers".

In the pale blue corridors of the clinic, the yellow skin and slow gait of a woman indicate that she has just emerged from a bath. Tatiana Shabunin is a dermatologist and she is keeping her husband company during his treatment.

She discovered Naftalan oil in her textbooks while at medical school in Moscow and has come out of professional curiosity and "for sheer pleasure".

Others come for medicinal reasons. The crude is said to heal the skin, treating conditions like eczema and psoriasis; the joints, easing rheumatism and arthritis; and the nerves. "Over 100 problems in all," Dr Zulfugar says.

However, the oil is almost 50 per cent naphthalene, a hydrocarbon commonly used as a moth repellent. This poses a problem because EU regulations deem it a potentially carcinogenic substance.

The doctor shrugs off these concerns, saying the limited exposure of eight to 12 minutes in the bath, and not more than one bath a day during a 10-day treatment, means his patients are not at risk. Millions of patients have used the Naftalan baths, he says.

In their 1980s heyday, 75,000 people visited the crude spas each year. That torrent became a trickle in 1988 when war broke out between Azerbaijan and ethnic Armenians in nearby Nagorno-Karabakh. Five of the six Soviet-era resorts became refugee shelters.

Azerbaijan has since experienced a new petroleum boom, emerging as a key transit route for oil from Central Asia to Europe. Gross domestic product grew more than 20 per cent a year on average between 2003 and 2007, making the economy one of the world's fastest growing. The country is so awash in oil that people are literally swimming in it – and Baku is cashing in.

"Look at this hill," says Hikmat Ibrahimov, the founder of the clinic. "When we started, there was nothing here." Today it boasts a power station, restaurants and cranes, many cranes.

In 2002, Mr Ibrahimov pulled off a coup by obtaining the right to transport the crude from the remote plains of the hinterlands to the very rich Azeri capital. "With President Aliev's help," he dutifully adds. Construction started on a second clinic this winter.

In the VIP bathroom, the 18-year-old bathboy, Ismael, helps the Russian rafter to the shower for his 30-minute scrubdown. It will take Ismael three months to earn the £300 pounds it costs for a 10-day treatment. He jokes that his client will be taking a few drops of black gold back to Siberia as a souvenir: Mr Shabunin's saturated skin will ooze crude oil for two or three days to come.

Azerbaijan: Land of black gold

*A former Soviet Republic, Azerbaijan lies at a strategic crossroads between the East and the West, sandwiched between Iran and Russia and straddling a region emerging as a key transit route for oil and gas from Central Asia to Europe.

*Its 8.7 million people are mostly Shia Muslims. They speak Azeri, which is closely related to Turkish, although Russian dominates the capital, Baku.

*Gross domestic product grew by more than 20 per cent a year on average between 2003 and 2007, making the economy one of the world's fastest growing.

*Ethnic Armenian separatists, backed by Armenia, fought a war in the 1990s to throw off Azerbaijan's control over the mountainous Nagorno-Karabakh region. An estimated 30,000 people were killed. The presidents of Armenia and Azerbaijan are expected to meet in Russia next week for talks to end the conflict.