Unique Tour, this tour is perfect for people for you that love to be in the nature, adventurers and explorers ! As is a Private Tour, you will decide the time to end the tour. Terceira Island, as volcanic origin presenting their morphological diversity, but maintaining some common geological traits. Its origin is associated with several volcanic eruptions, that occurred in the Alpine Orogeny; that remounts to the Tertiary Age to the present days, leaving an outstanding speleological heritage. So, we wish to share these several beautiful caves not open to the public (no man hand). The only 2 places that are open to public is Volcano Algar do Carvão and Christmas Cave. This places are only open in winter on Tuesday, Wednesday, Friday and Saturday. In summer every day is open. They are also closed on expecial occasions as Christmas days or special date.