a natural formation where a rock arch forms, with a natural passageway through underneath
a sub-category of natural arch, consisting of an arch that has formed over a water course
a rock formation shaped like a bridge and spanning a ravine or valley, especially one made by water working its way slowly through the rock. [AHDOS
Natural Bridge in Rockbridge County, Virginia is a geological formation in which Cedar Creek (a small tributary of the James River) has carved out a gorge of the limestone mountainous terrain, forming an arch 215 ft (66 m) high with a span of 90 ft (27 m). It consists of horizontal limestone strata, and is the remains of the roof of a cave or tunnel through which the creek once flowed. It is crossed by a public road, U.S.
