SLIPPERY ROCK - Soaring gas prices didn't keep a retired Slippery Rock man from completing his perimeter tour of the United States this summer.

In fact, Bob Lutz completed his round-the-country circuit without spending a dime on gas.

That's because he depended on the power from his own pumping legs to propel him. The entire trip was taken by bike.

Outlining the country in four separate trips over the past six years, Lutz, 61, reached his goal June 29, returning from a two-month bike hike.

His latest journey began April 1 in San Diego, Calif., and took him along the country's southern border to St. Augustine, Fla, before bringing him back to his hometown of Slippery Rock.

"Boy, it makes me feel good!" said Lutz of his accomplishment. "Some people say, 'You're crazy.' Some people say, 'You're amazing.' It's a big challenge to do that, especially unsupported."

By "unsupported," Lutz means that he was biking solo a majority of the 5,121 miles he traveled over the years. During this summer's trek and the previous one taken in 2003 on the West Coast from Canada to Mexico, Lutz traveled alone, supported only by those he met temporarily during rests and overnight stays.

His first two trips, from Maine to Florida and from Seattle to Slippery Rock by way of Toronto, were undertaken with groups on bike tours.

"It's not as difficult as you might imagine," Lutz said, "but you have to be in shape."

Being in shape was the reason Lutz got into biking in the first place almost 20 years ago. He is an avid skier, traveling to Salt Lake City four months of the year to participate in the sport, and initially biking was a way for him to maintain his condition on the off-season.

"I just fell into it," he said. Years later, his training is still that simple: "I just bike a lot. I'm never out of shape."

His top physical condition served him well during his bike trips, especially the one along the West Coast, when he passed over five or six mountain passes in Arizona and New Mexico alone. He was also pushed to his physical limits when encountering a head wind during most of his voyage across Texas, the second largest state in the union.

"The challenge is getting out there every day. It almost feels like a job," Lutz said. Even when you want to stop, you have to keep going, he said. "You don't have any choice. You're out in the middle of nowhere. I focus on what I'm going to see."

To plot his route and to ensure that he would not be in the "middle of nowhere" for too long, Lutz used specialized biking maps printed by Montana-based Adventure Cycling. Lutz was able to plan the distance of each day's ride ahead of time. His goal was to travel between 60 and 100 miles a day, depending on where he could find lodging for the evening, usually at a motel or campground.

It was in the evening or during quick stops at convenience stores during the day that Lutz had the opportunity to meet the locals. Meeting all the different people, he said, was his favorite part of the experience.

"People treat bikers like celebrities," he said. It wasn't unusual for someone he had just met to buy him a beverage or some food. Twice in Texas, people bought him dinner, and the newspaper in Comfort, Texas, even featured his photo with a caption detailing his venture.

"The people in Texas are probably the nicest people in the country," he said.

One man, Lutz said, even drove him to San Antonio to see the sites. Lutz had not mapped a route to that city ahead of time and would have missed out on it if not for the ride.

In the evening, Lutz was free to check out the museums and other sites and entertainment of whatever town he stopped in, and during his West Coast trip, he took plenty of opportunities to swim in the ocean. The ocean panorama was his favorite scene of the entire experience, he said, but he also particularly enjoyed the scenery while traveling along the Potomac River during his most recent outing.

Still, being on the road for months at a time becomes challenging, and when Lutz pulled back into Slippery Rock at the end of June, completing his six-year adventure, it was without regret.

"I was glad to be home. I wasn't so much tired of biking, but staying in campgrounds and motels, that gets a little tiring after a while," Lutz said.

His friends gladly welcomed him home and are continually amazed by his bicycle feats.

"The first time I heard him say he was going to bike to Pittsburgh, I thought he was nuts," said Francis Hensler, a friend since high school. "His trips got longer and longer. When he went with a group from Maine to Florida, we thought that was spectacular."

Hensler said Lutz accomplished a complete circuit of the country by putting forth the same devotion he puts in to all his projects.

"Whatever Bob puts his mind to do, he does it," Hensler said.

Having biked the four borders of the United States hasn't left Lutz without future goals in the sport, however. Sometime in the coming years, he would like to take a cross-country trip through the center of the country, and after that he has his sights set on Europe.

"Everyone says that's fabulous," he said.

For those inspired by Lutz, he has some advice: Ride your bike as much as you can; learn your bike and what you can and cannot do on it; and take at least your first long journey with a tour group. That should get you started toward something that few others accomplish.

"And it's a great way to see the country," Lutz said.