 Mérida preserves more important ancient Roman monuments than any other city in Spain, including a triumphal arch and a theatre.After the fall of the Western Roman Empire, during the Visigothic period, the city maintained much of its splendor, especially under the 6th-century domination of the bishops, when it was the capital of Hispania.In 713 it was conquered by the Muslim army under Musa bin Nusair, and became the capital of the cora of Mérida; the Arabs re-used most of the old Roman buildings and expanded some, such as the Alcazaba.