تعريف natural bridge في الإنجليزية الإنجليزية القاموس.
or natural arch Naturally created arch formation resembling a bridge. Most are erosion features that occur in sandstone or limestone. Some are formed by the collapse of part of a cavern roof. Others may be produced by entrenched rivers eroding through meander necks to form cutoffs. Still others are produced by exfoliation (separation of successive thin shells) and may be enlarged by wind erosion