Ustica Sireta Cave is located in zone C of the Ustica Island Protected Marine Area, before reaching Harp Point, we arrive at Sireta Point (secret), formed by hard blocks of lava, the coast previously low and jagged, rears up taking the shape of a semicircle. It contains the wreck of a vast excavated complex of which the Green Cave is part on the left side with its low entrance, on the right instead a sort of large cap, into which the sea penetrates it continuing its demolition work, the Sireta cave. Of the latter, only a part of the bottom remains, perfectly illuminated, with the shape of a hemicycle in the emerged part where it is wedged for about twenty meters and with an initial height of as many and climbing inwards. Blue reflections, large collapsed blocks in front of the entrance and a beautiful view from inside the Punta dell’Arpa.