Travel Puerto Rico - This is a picture of 'The Devil's Tower' in San Juan Puerto Rico. This picture is at Ft. El Morro right by the ocean. The used to be a working fort back when the country was being fought over between the Spaniards and the British. Now, it's a National Historial Site. Beside this fort, is San Cristobal, another fort used in the wars. All together, the people of the city of San Juan build a wall all around the city to protect it. Today, all of the wall that stands are the outer walls of the forts.