Cave Erosion
Natural bridges can form from natural limestone caves, where paired sinkholes collapse and a ridge of stone is left standing in between, with the cave passageway connecting from sinkhole to sinkhole.
Like all rock formations, natural bridges are subject to continued erosion, and will eventually collapse and disappear. One example of this was the double-arched Victorian coastal rock formation, London Bridge, which lost an arch after storms increased erosion.
Read more about this topic: Natural Arch
Famous quotes containing the words cave and/or erosion:
“Do you know how poetry started? I always think that it started when a cave boy came running back to the cave, through the tall grass, shouting as he ran, “Wolf, wolf,” and there was no wolf. His baboon-like parents, great sticklers for the truth, gave him a hiding, no doubt, but poetry had been born—the tall story had been born in the tall grass.”
—Vladimir Nabokov (1899–1977)
“Inter-railers are the ambulatory equivalent of McDonalds, walking testimony to the erosion of French culture.”
—Alice Thompson (b. 1963)