Grotta dell'Inferno, Natural cave in Muros, Italy.

Grotta dell'Inferno opens in Miocene limestone on the western slope of Monte Tudurighe, in the municipality of Muros at 320 m above sea level. Its entrance, 10 m wide and 5 m high, is hidden by the Badde Olia wood. A main branch runs 220 m, wide for three quarters of its length, and the whole system of shafts, branches and collapses reaches about 600 m.

Finds made since the first explorations include lithic and pottery artefacts from the Neolithic and several phases of the Nuragic civilisation, mainly the Bonu Ighinu culture. The most notable are a cardial ware sherd decorated with shell impressions and a bowl fragment with a star motif, now held at the Museo Sanna in Sassari.

The names Grotta dell'Inferno, grotta del Diavolo and grutta'e s'Inferru' link the cave to local devil lore. Finds from the first explorations, including cardial pottery impressed with a shell and a bowl fragment with a star motif, are kept at the Museo Sanna in Sassari.

Wear sturdy shoes and bring a flashlight when entering, as the ground is uneven and natural light does not reach deep into the passages. Guided tours are available during warmer months and help visitors navigate safely through this underground space.

The cave's concretions are scarce, damaged and darkened by visits since the second half of the 19th century, when bat guano was quarried here as fertiliser. Among the fossil remains found inside is the deer Megaceros algarensis.