The nuraghe is built on a hill, in a position of large domain, in the marble-limestone region of Trexenta, in southern Sardinia.
The Piscu is a majestic nuraghe complex, formed by a main tower to which a bastion with four corner towers was added. The monument is located inside a pentalobed antemural that defends the adjacent town. The structures are made of carefully processed limestone blocks arranged in regular rows. The main tower, circular (diameter 11.00 m; height 9.10 m), has the entrance facing south-east (width m 0.98), covered by an lintel (m 1.52 x 0.60 x 0.72) with an exhaust window above.
The rear corridor (length m 3.22; width m 1.10/1.40; height m 3.05), with an angular section, has two opposing niches (depth m 1.90; width m 0.90; height m 1.50 - width m 0.70; height m 1.60). The entrance leads into the large eccentric and circular chamber (diameter 5.20 m; height 5.00 m) - without subsidiary compartments - built with rough blocks placed on horizontal rows with the aid of reinforced wedges and mud mortar. There is no trace of the staircase, both in the hallway and in the room, so it is conceivable that access to the top of the tower was from the stands. The bastion (34.60 x 33.30 m) has an unusual layout: the recto-curvilinear curtains, in fact, connect four secondary towers, two of which are adjacent, so the general plan looks like that of a three-lobed, rather than a quadrilobed one. The added body is accessed through an open entrance to the south-east, with a corridor on the back of which there are two opposing niches. The corridor leads into the courtyard, with an irregular plan (10.40 x 3.20 m), to which the entrances of three secondary towers open: the one facing the keep and the two adjoining towers arranged to the left of it.
The adjoining towers have different dimensions: the front tower, similar in size to the keep (diameter 11.20 m), has an open entrance to the courtyard, oriented to the north-west (width m 0.75; height m 0.50) and surmounted by an lintel. The door leads into a trumped corridor (length m 1.88; width m 1.00/1.50; height m 1.90) that leads into the decentralized and circular chamber (diameter m 5.50; height m 3.00), equipped with numerous slits (width m 0.45; height m 0.70). In the walls of the room there are three niches and a room with a T-shaped plan that has on the right wall the entrance of a staircase that was supposed to lead to the upper floor. The small tower leaning on the north side (diameter 5.50 m) has a circular internal opening (diameter m 2.80) which is accessed through a short stoned passage (length m 2.10; width m 0.80/1.30). The tower built on the same axis as the entrance to the keep (diameter m 8.00) has a circular chamber (diameter m 3.80) - with slits - accessible from the courtyard through a rectangular entrance (length m 2.10; width m 1.00) facing the opening of the main tower.
The retrospect tower (diameter 8.00 m) has a circular opening without subsidiary spaces. In the curtain wall on the front, between the two elevation towers, a niche with a well is spared. Around the monument, there is an antemural that incorporates several towers, somewhat protruding from the profile of the connecting curtains: the tower to the east of the nuraghe has a circular plan (diameter 7.00 m) and an internal compartment (diameter 3.00 m) without niches.
The area between the nuraghe and the antemural is characterized by the presence of numerous circular and quadrangular huts with dividing septa.
The nuraghe has phases from 1400 to 1000 BC.

History of excavations
The building was excavated in 1860 by private citizens. The systematic exploration and consolidation of the complex were carried out between 1980 and 1988 by Vincenzo Santoni.

Bibliography
V. Santoni, “Nuraghe Piscu: the ancient and middle orientalizing, (Suelli-Cagliari)”, in Archaeology Bulletin, 3, 1990, pp. 145-148;
V. Santoni, “Nuraghe Piscu di Suelli: material documents of the medium-recent bronze”, in Sardinia in the Mediterranean between Middle Bronze and Recent Bronze, 16th-13th century BC: Proceedings of the III study conference A Millennium of Relations between Sardinia and the Mediterranean Countries, (Selargius-Cagliari, 19-22 November 1987), Cagliari, Edizioni della Torre, 1992, pp. 167-185;
V. Santoni, “Conservative and Restoration Interventions at the Nuraghe Piscu di Suelli”, in Proceedings of the conference Science of Materials and Cultural Heritage: Experiences and Perspectives in the Restoration of Nuragic Buildings, (Cagliari-Villanovaforru, 1990), Stef, Cagliari 1992, pp. 65-72;
V. Santoni, “Suelli, Nuraghe Piscu: the hut n. 4 of the Orientalizing Age”, in Etruria and central-northern Sardinia between the Late Bronze Age and Archaism: Acts of the XXI conference on Etruscan and Italic studies”, (Sassari, Alghero, Oristano, Torralba, 13-17 October 1998), Rome-Pisa, International publishing and polygraphic institutes, 2002, pp. 463-480; G. Lilliu, I nuraghi.
Prehistoric towers of Sardinia, preface by A. Moravetti. Nuoro, Ilisso, 2005, pp. 109-111, 267-269, 375, table. CIII.