Gruta das Mercês
The Gruta das Mercês is a cave located along the Canada das Mercês, situated in the civil parish of Feteira, municipality of Angra do Heroísmo, in the Portuguese archipelago of the Azores.
The cavern was created by volcanological forces that generated a lava tube, along a series of lava flows near the coast. It is approximately long, tall and wide.
