Its granite tower is twelve metres high and has two overlapping chambers that, quite exceptionally, still have their tholos roofs intact and an unusual, elaborate system of steps. The nuraghe Orolio, also known as Madrone, stands at a height of over 400 metres above sea level on a hill to the north-east of Silanus, about a kilometre from the village in the Marghine territory. It was originally a complex nuraghe, probably trefoil, but today only the truncated cone-shaped keep is still in excellent condition. You can enter the building from an entrance on top of which there is a mighty architrave and then a corridor will take you to the first room. Here, you will notice three niches, one facing the entrance and the other two positioned crosswise, creating a cross. The stairwell starts on the left, leading to the main room located on the second level.