Barranquilla is the fourth most populated city in Colombia, after Bogota, Medellin and Cali, and is the capital of the Atlantic province in the north of the country. 20 minutes from Baranquilla is the Castillo de Salgar built by the Spaniards in 1848 on the ruins of the older fort of San Antonio. It is located at a site that was considered very important and strategic to spot smugglers' vessels that were trying to avoid paying taxes. Later the office moved to Barranquilla and the castle become obsolete and was abandoned for over 60 years. In 1940 it was restored to be used as a recreational center by the Ministry of Education.