The town centre, with its characteristic houses with wooden rows of balconies, is medieval in origin and earned recognition as a Historic Site in 1978. Its main monuments, of different styles and periods, contrast with the seafaring sobriety of the old village, formed by narrow streets which are perfect for strolling through. The buildings of the church of Santa Marķa, from the 13th to the 15th centuries, the most significant example of Cantabria's Gothic architecture, and the castle-lighthouse, visible from all parts of town, are the most representative sights in Castro Urdiales.