If swimming pools and ponds have become too mainstream for a quick swim, perhaps it’s time to take a dip in the crater of an ancient submerged volcano, such as this natural lagoon on the Islet of Vila Franca do Campo in Portugal.

Top Places in Portugal

Portugal

Igreja de Vera Cruz de Marmelar

A chunk of the "true cross" is held in this small Portuguese church where modern day exorcisms are said to be common place.

38.2259, -7.6803

Pico, Portugal

Mount Pico

As the highest point in the Mid-Atlantic range this stratovolcano offers spectacular views.

38.4580, -28.3228

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Porto, Portugal

Igreja de São Francisco Catacombs

Ancient catacombs form the foundation for this Rococo orgy of a church.

41.1408, -8.6153

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This tiny island is a rocky crater formation off the coast of Sao Miguel. Its main attraction is the circular lagoon on the islet, which is broken up by a tiny channel that connects it with the ocean. The result is a clear and calm pool that is perfect for swimming and diving. 

The islet and this natural pool are accessible only during the summer and their stunning geography has made them a popular destination. Erosion through continuous exposure to wind and water have created different rock formations around the islet, including a fascinating column-like structure.

Over the years, the islet has helped whalers spot their targets and has also served as a military fort. In 1983, the unique location was declared a nature reserve to protect the endemic vegetation around the crater, as well as the crustaceans and birds who have made the islet their home.