El Morro 

El Morro is a landmark that was used to guard the capital of San Juan. The Spanish built El Morro to stop all invaders from entering the capital city. El Morro was built in 1539 by the order of King Charles I of Spain, a Spanish colonizer, and was completed in 1790. The building was built on an overhang at the top of the island, right at the edge of the Atlantic Ocean. This site was chosen because it overlooks the Atlantic Ocean; therefore, it has a great view of ships coming in and out from the harbor. It was chosen because of it's strategic location, which was used to prevent any intruders from entering the city. In the end, the landmark helped the Spanish keep both the English and the Dutch from entering Puerto Rico.  

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