3. Gruta do Natal

Gruta do Natal is one of the best-known lava tubes on Terceira Island and a highly recommended visit for understanding the volcanic origins of the island from the inside. It is a natural cave formed by ancient lava flows, which can now be explored through a well-maintained and straightforward interior circuit.

The visit to Gruta do Natal follows a route that is almost 700 meters long through the interior of the lava tube. The ceilings are high and there is very little elevation change. Throughout the visit you'll be able to see different volcanic formations that show how the lava gradually shaped this unique cave. It is a short visit, but very interesting and unlike any other experience on Terceira Island.

Gruta do Natal is located in one of the areas with the highest concentration of points of interest on Terceira. Very close by are the Furnas do Enxofre, the Negro Lagoon, and the Mistérios Negros Forest Reserve, where the PRC01TER trail through the Mistérios Negros begins — one of the most impressive hiking trails on the island.

It is also common to combine this visit with Algar do Carvão, as there is a combined ticket that saves you money, so we recommend including it as a must-stop when visiting the interior of Terceira Island.

Visitor information:

• Hours: January 1 to March 31 and October 1 to December 31: Tuesday, Wednesday, Friday, and Saturday, from 2:30 PM to 5:00 PM. April 1 to May 31: every day, from 2:30 PM to 5:00 PM. June 1 to September 30: every day, from 2:00 PM to 6:00 PM.

• Admission: €9 per person.

• Combined ticket: Gruta do Natal + Algar do Carvão for €15.

• How to purchase: tickets are sold only at the ticket booth, on a first-come, first-served basis (no reservations accepted).

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