Roman bridge over Tagus river

ALCÁNTARA: Roman bridge.

Built over the Tagus in A.D. 105. Constructed entirely of granite blocks, without the use of mortar, it is 194m/637ft long and 8m/26ft wide, spanning the river with six arches up to 58m/190ft high. Half- way across the bridge is a triumphal arch in honor of Trajan, on which in later times the arms of the Habsburgs and Bourbons were mounted. On the left bank of the river is a small Roman temple dedicated to the builder of the bridge, Gaius Julius Lacer.

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