The Roman bridge in Sommières is 190m long. It was built on the instructions of Emperor Tiberius at the start of the 1st century. It was restored in the 18th century. At the town end of the bridge is the gothic town gate known as the 'Tour de l'Horloge'. Only 7 of the 19 arches can be seen, the others lie beneath the town where they act as cellars.References:
The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.