Naveta
A naveta is a form of megalithic chamber tomb unique to the Balearic island of Menorca. They date to the early Bronze Age. They have two vertical and two corbelled walls giving them the form of an upturned boat, from which the navetas take their name.
The largest example is the Naveta d'Es Tudons which is around 4m high, 14m long and 6.4m wide.
The first author who wrote about this structures was Juan Ramis in his book Celtic antiques on the island of Menorca, which was edited 1818, being the first book in Spanish language entirely devoted to Prehistory"