What is the difference between a "bridge" and an "arch"? I asked that question at the visitor center.

A bridge is created by water flowing under it, eroding the sides until it collapses from above. An arch is formed from other forces in addition to water. Arches result from cracks and stresses caused by ancient land movement. Water can widen the cracks until they break away.

Natural Bridges National Monument features three prominent bridges, each created at different times. Overviews are located short hikes from the park road, though the more ambitious can hike down into the canyon and directly up to the bridge.