Gruta das Agulhas

Gruta das Agulhas is a cave located along the promontory of Ponta dos Coelhos, in the Bay of Refugo, in the civil parish of Porto Judeu, in the municipality of Angra do Heroísmo, the Portuguese archipelago of the Azores.

The cave is situated along the coast of Salga, along the high cliffs of the promontory, formed from an accumulation of lava flows. It was formed during the eruption of the volcano associated with the Algar do Carvão, which flowed to the sea, arriving at the coast of Serretinha, in the civil parish of Feteira. The flow spread to Porto Judeu, forming a coastal geomorphology of black basalt of large dimensions, arribas and coves of dangerous cliffs.

Source: Wikipedia