Torre de Ses Portes, Coastal watchtower in Sant Josep de sa Talaia, Spain.

Torre de Ses Portes is a two-storey defensive tower of limestone masonry with corner stones set in lime mortar, built on uneven ground. Its exterior is smooth and unadorned, with four openings for ventilation, and a spiral staircase of single-piece steps leads from the ground floor to the platform. It stands at 11 metres above sea level between Es Cavallet and Ses Salines beaches, in the Ses Salines natural park.

The tower was built in the late 16th century to defend against pirates. The valuable salt ponds nearby made the area a frequent target for raids, driving the need for this coastal fortification.

The tower reflects Mediterranean coastal defense design and commands views over the strait between Ibiza and Formentera. Standing here helps you understand how vital this location was for seafaring.

You can reach the tower via a sandy path between Es Cavallet beach and the salt ponds of Ses Salines Nature Reserve. The walk is straightforward, though you'll want footwear that handles sand.

The four openings on the smooth outer wall are not windows but loopholes for ventilation. Inside, a single-piece stone spiral staircase links the ground floor to the platform, and from the top you look over the Es Freus strait between Ibiza and Formentera.