An imposing Gothic masterpiece, the Cathedral of Valencia consists of three naves, a polygonal apse and monumental dome. Construction began in 1262 and finished in 1702, though before it was a cathedral, it was the site of a mosque and a Roman temple. The cathedral's three doors reflect the mixture of styles: the Palau (palace) door is archaic Romanesque mixed with primitive Gothic; the Door of the Apostles is pure Gothic, and the Hierros Door is Baroque. Every Thursday at midday, the Door of the Apostles is the site of the oldest tribunal in all of Europe, the Tribunal de las Aguas (Water Court), which resolves the conflicts arising over the use of water in the nearby fields. Another outstanding feature is the Gothic bell tower, known as the Miguelete, whose 207-step stairway takes you up to some of the best views over the city. The cathedral also houses the Catedralicio Diocesano Museum and the Santo Cáliz Chapel.