Bridges form through the erosion of rock by streams or rivers. This window or arch formed from a combination of processes. Frost wedging, the expanding of cracks in rock as water turns to ice, weakened the rock. Dissolution, the chemical dissolving of rock by rainwater, chewed away at the top and sides of this wall of rock. Finally gravity pulled loose the weakened pockets of rock at the center creating the hole you see. Thus, Bryce Canyon's 'bridges', including Natural Bridge, are spectacular examples of arches that, like the hoodoos, are constantly at risk of destruction as the forces of erosion continue to wear the rock away.
In the southern corner of the parking lot you will notice a small stand of Quaking Aspen. Historic photographs suggest that aspen were much more common throughout the southern portion of the park prior to intense fire suppression efforts of the past 75 years. Aspen are easily shaded out by spruce and Douglas Fir. You will notice several areas of burned trees as you drive through the park. This is evidence of our prescribed fire program. By returning small and safe fires to the ecosystem we can slowly restore a natural mix of forest types, providing better habitat for a greater diversity of animals. Also near the parking lot you might find Markagunt Penstemon.