Biniac has two circular burial navetas that were used around 1400 B.C. and are from an earlier period than the long rectangular constructions like the Es Tudons and Rafal Rubí navetas. The east naveta was built on bedrock and has only one oval-shaped chamber, accessed via a perforated stone slab. Several slabs that had fallen over were found inside. The west naveta is also oval-shaped and the wall on the south side has dry stone cladding, clearly added at a later date.
References:The Broch of Gurness is an Iron Age broch village. Settlement here began sometime between 500 and 200 BC. At the centre of the settlement is a stone tower or broch, which once probably reached a height of around 10 metres. Its interior is divided into sections by upright slabs. The tower features two skins of drystone walls, with stone-floored galleries in between. These are accessed by steps. Stone ledges suggest that there was once an upper storey with a timber floor. The roof would have been thatched, surrounded by a wall walk linked by stairs to the ground floor. The broch features two hearths and a subterranean stone cistern with steps leading down into it. It is thought to have some religious significance, relating to an Iron Age cult of the underground.
The remains of the central tower are up to 3.6 metres high, and the stone walls are up to 4.1 metres thick.