Located on the Plaza de la Seo, the cathedral is referred to as la seo ("the see") to distinguish it from the other cathedral, el pilar. La Seo has originally been constructed one the site one of the first mosques during the Moorish domination of Aragon, built perhaps as early as the 8th century, and destroyed to make way for a romanesque church in the 12th century. Zaragoza became an independent diocese in the 14th century and the church became its cathedral, immediately being afforded renovations in the gothic and moorish (mudéjar) styles. Many other reconstructions followed, due to both changing tastes and architectural necessities, as parts of the cheaply-built cathedral began to fail over time, including the collapse of the its in the 15th century.In the 17th century, the church has been involved in a canon law battle with the newly-reconstructed Basilica of Our Lady on the Pillar over which should be the seat of the diocese and thus the cathedral, which finally saw Pope Clement X declare them joint cathedrals with special provisions to make sure both enjoy equal status. La Seo is now a mixture of styles spanning between 12th and 19th centuries, and features an exquisite collection of tapestries. Entrance closes sometimes during the day when there's mass.