Here's a little compilation of my friends and I jumping at the Perrine Bridge in Twin Falls, Idaho. This is the only bridge in the US that it is legal to jump off at any time. It stands at 480 feet and is one of the most popular BASE jumping spots around. Jumpers come from all over the world to make their first jumps, learn new tricks and dial in aerials. Bridges are arguably the safest objects. Unlike cliffs, antennas and buildings, an off-heading opening (having your parachute open any direction other than forwards) doesn't require instant action to avoid injury. You have a much larger margin for error. Letting you focus more on the learning aspect. Hitting this object would take some effort. I've been training for a building jumping event in Malaysia in September. This is the perfect spot to push your comfort levels. A measly 7 hours from Moab, I've made it up here 8 times since April. Its a playground for adults. Well... slightly off adults. :) 

BASE jumping in Idaho.