Santillana del Mar is a municipality and a town in the autonomous community of Cantabria (Spain). It is located on the west coast of Cantabria, a region of which is its eastern end.Santillana del Mar is one of the towns with the greatest historical-artistic value in Spain, which makes it one of the most visited and attractive places in the region.It is known for its medieval towers, Renaissance palaces and the Romanesque collegiate church of Santa Juliana. To the southwest of the city, the Altamira National Museum and Research Center focuses on prehistoric life and art discovered in the nearby Altamira Cave. This Cave, described as the Sistine Chapel of Rock Art, it probably contains the most famous prehistoric paintings in the world.