Travis Pastrana had driven the car only once or twice before, and now the extreme sports legend wanted to take his brand new Subaru WRX Impreza for a quick test drive. He pulled the car from the driveway of his Davidsonville mansion and steered it down a steep hill leading to his 20-acre property.

He pushed the pedal to the floor, and the car revved to 30 mph . . . 40 mph . . . 50 mph, its wheels screeching around a tight curve. Pastrana kept his foot on the accelerator until the car came within 50 yards of a large shed. Then he jerked up the emergency break, hurling the car into a 300-degree tailspin and a sudden stop.

"Not bad," Pastrana said as he climbed out of the car, "but I should have been going faster."

Pastrana has long lived in defiance of fear and inhibition, and that lifestyle has simultaneously built him up and broken him down. At 22, he is considered perhaps the greatest motorcycle rider ever. His fearlessness has allowed him to draw a seven-figure salary, live in a house featured on "MTV Cribs" and enjoy more than two dozen sponsors willing to reward him for almost any death-defying stunt. He helped push extreme sports and their premier event, the X Games, into the lucrative mainstream of American popular culture during the last decade.

But his audacity also has caused 18 serious concussions, more than 50 broken bones and 11 knee surgeries. He suffers short-term memory loss. At an age that most of his peers start their working lives, he is preparing to make a major transition, from the career that made him famous -- motorcycle racing -- to the relatively safer field of auto racing.

That's not saying that his near-reckless disregard of human limits will change.

"It's crazy," Pastrana said, "but the most exciting stuff happens when you turn off your brain and forget about fear."

Pastrana credits that strategy for much of his success during a landmark career that has made him the preeminent celebrity in a handful of sports. He has excelled in outdoor motocross and arena-based supercross, both forms of dirt-bike racing. He has won 28 of the 30 events he has entered in freestyle, essentially motorcycle jumping.

His fearlessness, though, extends far beyond official races. He built a playground in Davidsonville that allows him to indulge -- and extend -- his thrill-seeking. The house features a pool, a hot tub, a big-screen television and a full gym with a sauna, but Pastrana and his friends spend most of their time outside, on property Pastrana purchased more than five years ago.

A tour of Pastrana's back yard is a long lesson in carnage. There's the massive, water slip-and-slide running from the house to the garage, where Pastrana watched two friends suffer concussions and another incur a crushed vertebra. "It's so fun though," Pastrana said, "that we still use it a lot."

There's the spot on the dirt bike trail where Mike Jones, a close friend, stopped breathing after he landed on his head while trying a back flip on a 220-pound bike. He foamed at the mouth before a medevac crew saved him. "I still don't remember that accident," Jones said, "or anything that happened during the next 10 days."

In the back corner of the woods, there's the junkyard of three cars, one jeep and a bus -- all of which were badly damaged during videotaped jumps done solely for entertainment. The jeep fared the worst. Pastrana tried to fly it 50 feet from a jump to a landing pad. Instead, the jeep fell five feet short and nose dived into the ground. "That was a nasty crash, even for Travis," said Chris Haynes, one of three friends who lives with Pastrana rent-free, "but I don't think he even got a concussion."

And, for a grand finale, there's the property's primary landmark: a gigantic foam pit in which injuries happen constantly despite every attempt to prevent them. The pit covers 900 square feet and is 10 feet deep, making it the largest foam pit on the East Coast. It took 45,000 blocks of foam to fill, at a cost of $1 a piece.

Getting into the pit is simple: Pastrana and friends jump a vehicle from one of three ramps -- one pushed directly against the pit, one 40 feet back, another 75 feet away -- into the soft cushion. Getting out of the pit involves considerably more work. The rider must hook his vehicle to a large crane that hovers over the pit. The crane then pulls the bike out of the pit and lowers it slowly to the ground.

Pastrana lauds the foam pit as the safest place in the world to jump, but even in the foam, injuries are commonplace. Pastrana requires all guests to sign a waiver before they do just about anything on his property. Last year, Pastrana's mom, Debby, broke her neck in the foam pit after landing awkwardly while trying a flip on a motorcycle driven by one of Pastrana's friends. She recovered.

In total, four people have been rescued by helicopter from Pastrana's house -- including two during one memorable day last year. At least two dozen other times, friends guessed, visitors have left Pastrana's house and headed directly to the hospital.

"I honestly believe angels must be looking after that place, because otherwise people would have died," Debby Pastrana said. "So many wild things happen there."

So many wild things -- even in just one day. Take, for instance, Sept. 24. As usual, Pastrana was hosting more than 15 people at his playground, an eclectic intermingling of 10-year-old neighbors wearing their soccer jerseys and pro motorcyclists wearing sponsored gear. And typically, Pastrana pushed nearly every visitor to obey the household rule: Forget about fear and push your limits.

That's how Kyle Ives, a mohawked 11-year-old visiting from Florida, managed to back flip a 120-pound motorcycle for the first time. That's how Jolene Van Vugt, a 25-year-old professional rider from Ontario, became the first woman ever to complete a back flip into foam on a 220-pound bike. And that's how Bill Van Vugt, Jolene's 60-year-old father, found himself pale and wide-eyed behind the wheel of a motorized go-kart.

Pastrana had pushed the go-kart out of his garage moments earlier, then persuaded his gray-haired visitor to strap himself into the driver's seat. This stunt would be perfectly safe, Pastrana promised the nervous driver, but his instructions hinted otherwise.

He told Van Vugt to accelerate the go-kart to about 30 mph, then launch it off a steep, 12-foot ramp and into the foam pit. The stunt, Pastrana said, would send Van Vugt flying 20 feet into the air before landing him softly in the foam pit. Only after the frightened man drove off did Pastrana mention any other possibility.

"We better get him out of that pit quick," Pastrana said. "The go-kart is hot, and it could easily catch fire."

Van Vugt emerged from the foam 30 seconds later, smiling and shaking his head.

"Every day around here, somebody tries something they never thought they'd do," Pastrana said. "If all you're doing is being safe, what are you going to accomplish?"

Pastrana learned early that high risks paid off in high rewards. His parents bought him his first motorcycle at 4, and he started competing nationally at 7. He developed into the perfect ambassador for extreme sports: a handsome, articulate kid who impressed adults, and an aggressive, daring athlete who left peers slack-jawed.

At 15, Pastrana won a gold medal at the 1999 X Games. Then, in celebration, he jumped his bike 80 feet into the San Francisco Bay, a stunt that drew national attention.

Pastrana and extreme sports, intertwined, have thrived together ever since. Pastrana signed a record motocross contract when he turned pro at 16, worth about $200,000 in base salary plus $25,000 in incentives for each win. He built a stable of mainstream sponsors -- Suzuki, Subaru, Red Bull, Alpine Star, Thor, Michelin and others -- that also paid him in incentives and appearance fees, boosting his total salary closer to $2 million. He appeared on Letterman once and Leno three times. He put out videogames and shot his own extreme highlight movies, with last year's video selling 80,000 copies at $24 each.

The X Games, benefiting in part from Pastrana's fame, vaulted from ESPN to ABC, while Fox and NBC created their own extreme sports programming. Freestyle -- a fringe sport that barely existed before Pastrana took over as its star -- is now televised by a major network about once a month, and its top four or five athletes make seven-figure salaries.

"He's so big now that his sponsors pay him big money for being a celebrity, not a rider," his father, Robert, said.

But for Pastrana, the sacrifices mounted just as quickly: A week after he turned 15, Pastrana came up short on a 130-foot motorcycle jump in Lake Havasu, Ariz., and crashed into a ramp at 65 mph. It took five blood transfusions to stabilize him, and he spent three months in a wheelchair. During the year after he came back from that injury, he broke bones six times.

"Let's put it this way: I would venture to say that, from the neck down, Travis is closer to 55 or 60 years old than 20," said Todd Jacobs, Pastrana's live-in trainer for two years.

Only concussions worry Pastrana. He wears a helmet when doing nearly anything active, but he has still suffered 18 serious head injuries. "When you're falling from four stories with a 220-pound bike," Pastrana said, "a helmet only does so much."

Friends said Pastrana already suffers some short-term memory loss -- "He'll call to ask me if I want to have lunch in Maryland when I just told him I'm in San Diego," childhood buddy Chris Alton said -- and it could continue to get worse.

The risk of head injuries is one reason Pastrana has decided to race cars. Having already helped build one sport, Pastrana said, why not try to establish another? He's shown promise in rallying -- auto racing that takes place on regular streets closed to the public -- finishing second in a national competition with 60 entries this season.

"He's so good that we could make a run at the title next season," said Christian Edstrom, Pastrana's rally co-driver.

Pastrana said he is safer in a car, too, although his recent results suggest otherwise. In his last rally race, Pastrana took a sharp turn at about 110 mph, rolling the car eight times. He walked away with what he described as a minor concussion.

But no matter what Pastrana raced, friends said, safety would probably elude him. His off days, after all, are filled with as much danger as his race days. He sky dives. He skateboards. He climbs a 30-foot rock wall in his shed. He rides a mechanical bull. He tries to jump buses 50 feet through the air.

He has several four-wheelers at his house, too, but Pastrana actually prefers two-wheeling. It's more of a thrill, Pastrana demonstrated, to drive a four-wheeler when it's balanced only on the right two wheels.

"Some stunts and tricks go against everything you've ever known," Pastrana said. "You almost have to just stop thinking. That's when you really make progress."

"It's crazy, but the most exciting stuff happens when you turn off your brain and forget about fear," says Travis Pastrana, 22, shown on a typical day in his back yard.Travis Pastrana, below right, and close friend Mike Jones check out video of a stunt they filmed at Pastrana's home. Both Pastrana and Jones have suffered their share of injuries, one of which caused Jones to stop breathing.Travis Pastrana has helped vault the X Games into the mainstream of American popular culture. His success in extreme sports landed him a $200,000 contract at age 16.