Lagoa do Fogo (São Miguel).

Fills the collapsed caldera of the Água de Pau Massif, Lagoa do Fogo is the highest and most pristine crater lake on São Miguel. Unlike other Azorean lakes, its shores are entirely undeveloped, protected by strict conservation laws that preserve the surrounding ancient laurel forest and endemic plants. Visitors can take in the dramatic, cloud-swept views from high-altitude viewpoints like Miradouro do Pico da Barrosa, or hike down the steep, 30-minute trail to the quiet, white-sand pumice beach at the water's edge. While swimming is strictly prohibited to protect the delicate ecosystem—which supports rare bird colonies like yellow-legged gulls—the reward here is the raw, silent volcanic landscape, often felt most intensely when the Atlantic mists roll over the caldera walls.