Along the route, besides the trademark red-rock cliffs and desert landscape, riders pass the ruins of an old stagecoach station, a wall of dinosaur bones, several towers, the Tusher Tunnel and Uranium Arch.

McFarland said he finds that people enjoy ATVs because they are easy to drive, riders are out in the open as opposed to confined inside a vehicle and they fit well into a family activity.

"Along with guided tours, we also offer rentals. Some people prefer to be off on their own. Along with the ATVs, we also rent satellite phones and GPS units, just in case people run into trouble somewhere along the trail. There are a lot of areas to ride," he explained.

A two-hour guided ATV tour runs $79. Children can ride for half price.

Jean Seiler, marketing director of Ruby's Inn near Bryce, said the number of visitors coming to the inn with ATVs in tow has increased sharply in recent years.

"So much so," he said, "we've created a series of detailed trail maps showing people where they can ride, either for a few hours, if they choose, or for several days."

The National Park Service at Bryce is also producing a large for-sale map of the regions showing ATV trails with detailed information on routes, sights and time commitments.

Other areas of the state have produced or are in the process of producing ATV-specific maps showing riding opportunities.

Paul Burningham, manager of Honda of Salt Lake, said sales on ATVs in the Salt Lake area are still strong, but not as strong as they were a few years ago.

He attributes some of this to the fact that back when sales were strong, people were buying multiple machines and trailers, "and now what they're doing is replacing those machines. We're selling one unit here and there. These are the machines with all the upgraded features.

"Price was also a factor. A person can by two decent ATVs and trailer for around $10,000. Two snowmobiles and a trailer, by comparison, will run about $23,000."

Prices run from $3,200 to $7,800 for a fully loaded ATV.

Safety has, of course, always been an issue. Early studies showed that the real reason for the number of ATV injuries was that people felt safer on an ATV because it did not tip like a motorcycle and were therefore not as careful as they should have been. The study also showed that in most cases people involved in an ATV accident were not wearing any type of safety equipment, including a helmet.