It's interesting to look into differing beliefs. An outing to Santa Maria Church is a fantastic way to appreciate one of the local religions.
This Castro Urdiales house of prayer is a good place to begin your day of sightseeing. There's lots to see close by, including Orinon Beach, La Arena Beach, and Playa Pocillo de los Frailes. Take your time at Santa Maria Church before heading to these other fine attractions.