Nuraghe Losa is just south of Abbasanta, alongside, and signposted from, the SS131, though on a convoluted junction.
As you pull off the slip road, there's a building 50m or so to the right; this is the ticket hut, but also shop, bar etc. It's managed by Cooperativa Paleotur, and costs 3½euros to enter (reductions available). Open 09:00 - 19:00 (17:00 in winter). For once, my attempt at Italian was answered in English, and tickets and info leaflets in hand, we walked back to the turning and up the track to the main gate, about 200m in total.
The complex is enclosed by a wall, ovoid in shape and approximately 300m x 200m. Just past the gate, there's an exhibition of funery urns to the left, gathered from all over the site; Beardy found loads more of these in the long grass behind the museum huts. The track takes you through the south east entrance; there are 3 more - one opposite, and two with oval towers at the apices of the ramparts. A village within the enclosure, thought to be late Bronze Age, has only been partially excavated.
But the main attraction is the nuraghe itself. It's a trilobate structure, with huts and a curtain wall surrounding it. The upper floor has collapsed, but it's still an impressive 13m high.
The main entrance is almost hidden by a round hut (Cap 1 on the plan) with several niches and recesses in its wall. In the actual nuraghe, there's no central courtyard at we'd seen at Santu Antine, instead there's chamber C to the right and chamber B to the left. Going straight ahead, there's a niche to the right with a flight of steps opposite it, then on through to the main tholos chamber with 3 wall niches, one opposite the entrance and the others on the opposite sides, forming a cross shape.
The third smaller tower can only be reached from the small northerly entrance. It as a (gated and locked) stairway that connects back over the summit of the nuraghe.
The stairs are worn to more of a sandy uphill track, clockwise round the main tower. The smaller towers, E and F on the plan, and their connecting wall, are thought to be a later addition.
There's a modern hut in the south of the enclosure with an exhibition of finds from here and other local sites.
The site has been dated to as early as 1400 BCE; it was investigated in 1898 and again in 1915, but the main excavation and restoration works were carried out between 1970 and 1976.