Volcano Surfing (From David Wilson).

Jagged ash, stinky gas, shoe-melting heat: on the surface, an active volcano's attributes make it a poor platform for sport, even the extreme kind. But "volcano surfing" or "ash boarding" exists and consists of what you expect: surfing down the side of a volcano.

Bare bones

All you need is a metal-bottomed board and nerves of steel (or a streak of insanity). Like a sledge-rider, you start by slogging up your volcano's sooty slopes on foot.

Rough cut

Then, like a sandboarder, whoosh!

You skid downhill, sitting or standing and trying damn hard to keep your balance. Because wiping out hurts, at the risk of resembling a mad scientist you should wear protective gear — boiler suits and goggles. Only lunatics wear bikinis.

Pyromania

Speaking of lunatics, in July 2008, after leaving an offering for the Hawaiian fire goddess Pele on a nearby beach, Hawaii-based pro-surfer C J Kanuha approached the world's most active volcano: the Big Island's Kilauea.

Positioned by a canoeist and a jet skier, Kanuha paddled as close as he dared, edging within just 6 metres of the lava. Reportedly thrilled by the experience, he then beat a retreat from the water that reached 200°C in places, melting the wax on his surfboard and peeling skin from his legs.

Kings of Leon

If you fancy a crack at volcano surfing without being boiled, the volcano to visit is Nicaragua's Cerro Negro (Black Mountain). Since 2005, over 13,000 adventurers — including five Survivor contestants — have surfed Cerro Negro, according to tour firm Bigfoot, which runs sessions on plywood boards (a better vehicle than mattresses, which have been tried).

Miracle birth

Charred and bare, Cerro Negro stands some 30 kilometres from the northern Nicaraguan colonial city of Leon. Like a miracle, Cerro Negro just appeared in 1850 in the heart of a cornfield.

Ever since, the sulphur-stained, wind-buffeted oddity without a speck of vegetation has been growing. Now, Cerro Negro stands over 700 metres tall.

Vicious temper

Despite its barren looks, Cerro Negro has erupted over 20 times. That makes it volatile compared to your average volcano, which is content to let the grass grow.

Cerro Negro last erupted in 1999, vomiting rocks and sending farmers scurrying. Even now, smoke and gas spew from its various vents. You can smell the sulphur.

When, after a 45-minute hike, you reach Cerro Negro's seething peak, you may admire the local national park's lush contours. In the meantime, in case your soles melt, you must keep moving and deflect the advances of updraft-borne stinging insects.

Speed demons

When the time comes to unwind, go with gravity. And unless you want to eat granite for breakfast, keep your mouth shut. Spine straight. Lean back. Smile for the radar gun!

During your eight-second ride, you will travel far faster than lava — up to 82 kilometres an hour, unless you are French extreme speed cyclist Eric Barone.

Red baron

In May 2002, on a first run down the steep lava bed, sat astride a standard mountain bike, Barone smashed the world record he set there two years before, clocking 163 km/h. His second run, on a specially modified bike, ended in horror. Apparently striking a rock, his bicycle snapped in two — the one-time Sylvester Stallone stunt double flew downhill.

Barone broke several ribs and his sternum, but triumphed. When the crash happened the action hero nicknamed the Red Baron had crossed the speed sensor, clocking 172 km/h.

Cuties

Unlike Barone, who is now nudging 50, most of the everyday speed freaks in overalls who zoom down the slopes are tousle-haired 20-somethings. The youngest ever, according to Bigfoot, was 12 (too young to do an official tour). The oldest was a Swedish 74-year-old, who must have been tough.

Raw nerve

Deceptively, the uploaded clips that you see make surfing Cerro Negro look like a party. Do not underestimate the courage it takes to face the dirty granite dust sharp as broken glass, plus the plunging gradient and heat of up to 40 degrees — damn hot in a boilersuit.

One-up

After rocketing down from the summit, you may well be cut, but one-up on those wussies who think that surfing cold wet waves is exciting.

Ballistic

Surfing Cerro Negro just might be the ultimate thrill ride — the mega-adrenalin hit which extreme sports addicts crave and perpetually seek. The quietly seething magma mountain could erupt any second.

Getting there

The nearest commercial airport to Leon is in the country's capital, Managua. From Managua, you can easily hire a rental car and drive the remaining 90 kilometres along a new highway. Or you can take a bus from Mercado Israel or the microbuses that leave from La UCA (La Universidad de Centro Americana).

For more information check out Bigfoot Nicaragua, Tierra Tour or Tours Nicaragua. The cost is about $30 and the duration about five hours. Expect a dawn start.