The document provides details about the history and architecture of Avilés town and some of its important buildings. It describes how in 1155 Alfonso VII granted Avilés a municipal charter, which allowed the town to develop greatly and become the first coastal village in northern Spain. It grew around its port, with two population centers of Sabugo and Avilés separated by the Tuluergo river. The village built defensive walls in the 12th century and the Franciscan Church was the first to be constructed. Traders and sailors lived in Avilés and it became an important center for salt storage and trade. The document also provides architectural details about the Franciscan Church and Old Sabugo Church.