Explore the unique natural history and geology of Terceira Island
The genesis of the Azores is imprinted in 1766 volcanoes, nine of which are still placidly active. In the subsoil, there are almost 300 known volcanic cavities, in the form of caves, algares and crevices. In the landscape, you'll find dry calderas, crater lakes, fumarolic fields and hot springs. The remains of volcanic activity assume spectacular and easily visited forms, particularly in Terceira.

Algar do Carvão
In the underground world, the highlight is the “Algar do Carvão”, remnants of an old volcanic conduct that dazzles with its spatial immensity. From its vaulted ceiling hang remarkable silica stalactites, the largest in the world. This popular spot is a natural reserve with limited visiting hours, so be sure to plan ahead and put it at the top of your list.

Gruta do Natal
The lava tube of “Gruta do Natal” marvels with the succession of narrow and long corridors and the different shapes and colors that take over the walls, floor and ceiling, transforming the cave into a mystical place.

Furna do Enxofre
On the surface, the “Furnas do Enxofre” (Sulphur Pits) are the eloquent testimony of the power of the Azorean volcanism: the landscape is dominated by fumaroles surrounded by reddish-colored terrain, which contrasts with the green of the mosses and other vegetation. The atmosphere is hot and with a peculiar smell... of sulphur.
Explore all this and more on this fascinating tour!