Cala Sant Esteve is located five and a half kilometers from the center of Mahón and two kilometers from the Castle (formerly the Sant Felip district), to the right of the harbor entrance. It is a small inlet, 650 meters long and 50 meters wide, occupied by two buildings of great historical interest: to the left, the Castle of San Felipe, built by the Spanish in the 16th century, and to the right, Fort Marlborough, built by the British in the 18th century. Outside the cove, on a hill to the right of the harbor entrance, stands the Penjat Tower, dating from 1789. This string of structures had the sole purpose of protecting the entrance to the port of Mahón from a point considered a true Achilles' heel for its defense. Not surprisingly, Cala Sant Esteve was the usual entry point for pirate raids, including Barbarossa's in September 1535.