Monte Perda Liana, Limestone summit in Ogliastra, Italy.

Monte Perda Liana is a 1,293-metre limestone and dolomite tower in the territory of Gairo, on the border between Ogliastra and the Barbagia di Seùlo. Its vertical walls, about 50 metres high and roughly 100 metres across, rest on a truncated cone of arenaceous rock, itself set on Palaeozoic schists. The tower is split by vertical fractures into large prismatic blocks.

The dolomite tower formed 130–150 million years ago from marine sediment laid down underwater. The cone-shaped base rests on Mesozoic sandstone, while the lowest section consists of Palaeozoic schists 360–500 million years old. Vertical fractures split the limestone walls into large prismatic blocks.

The name combines the Sardinian perda, a rocky mass, with liana, which some trace to the Nuragic Iliensi who gathered at the foot of the peak; others link it to the smooth rock or to the corbezzolo (olione in Sardinian) once covering the slopes. The tower is visible from Nuragic sites such as Serbissi at Osini and Ardasai at Seui.

The summit is reached by a third-grade climb on the east face, requiring climbing ability and proper equipment; fixed anchors are best avoided because the rock is fragile. Marked hiking trails, with a waymarking system, run around the mountain, and the Transardinia walking and cycling route leads into the area.

The name Perda 'e Liana may come from the Nuragic Iliensi people, who gathered at the foot of the peak; the tower is visible from their nuraghi, such as Orruinas at Arzana and Serbissi at Osini. Others link it to perda, Sardinian for a rocky mass, or to the strawberry tree, olione, once covering the slopes.