(CBS News) With the introduction of tandem BASE jumping, an extreme sport is taking a turn toward the mainstream.
Recently, extreme sports professionals and amateurs alike took part in the annual Bridge Day at the New River Gorge bridge in Fayetteville, W.Va. "Bridge Day" is the largest event in the world dedicated to BASE jumping, and the bridge is transformed into a launch pad as spectators watch jumpers hurl themselves into the water hundreds of feet below.
This year, 450 jumpers from 41 states and 10 countries participated in Bridge Day. More than 1,000 jumps took place, with eight tandem jumps and 24 catapult-propelled jumps among them, and only three minor accidents -- involving wrist and ankle strains -- occurred.
Illegal in most parts of the U.S., BASE jumping is a free fall parachuted jump off a fixed object. BASE stands for the objects from which the jumps must originate: a building, antennae, a span (like a bridge), or a the earth itself. The sport is often compared to skydiving, though some say the launch points and length of free fall make it more dangerous.
Mark Kissner has been jumping out of planes or off of objects for two decades, and calls BASE jumping both more intense and more serene that skydiving.
"In an airplane, it's loud," Kissner explained. "The engine's running, the wind's rushing, and so you're going out into a noisy environment where there is already a lot going on. Versus BASE, you're just standing on the edge, it's completely quiet, there's no motion ... you're just really at one with yourself and the object you're on...you're stepping off into nothing."
Few people -- professional thrill seekers like Kissner aside -- have had the opportunity to experience BASE jumping because it requires a high level of expertise and can be costly. In most states, participants are required to have at least 100 certified solo sky dives before they can make a solo base jump.
Two years ago, Kissner founded the first-ever tandem BASE jumping company, in Twin Falls, Idaho, with the hope of opening the sport up and lowering the cost for new participants.
And Bridge Day 2012 offered many amateurs the chance to BASE jump for the first time, including 68-year-old Ronnie Franklin, who served as a paratrooper in Vietnam and was able to cross BASE jumping off his bucket list this fall.
BASE jumping enthusiasts hope the tandem trend will open the sport to a wider set of participants, similar to the growing popularity of tandem skydiving seen in the 1990s.
For more from Kissner and to see Ronnie Franklin's first jump, watch the video above.