From this formidable 18th-century defence tower on Ibiza's southernmost tip (a 20-minute walk from the south end of Es Cavallet or Platja de Ses Salines), you'll glimpse the islands that speckle the Es Freus strait separating Ibiza and Formentera. Among them are Illa des Penjats (Hangman's Island), where captured pirates were once sent to the gallows, and Illa des Porcs (Pigs' Island), where plump pigs smuggled over from Formentera were once kept.