The ceiling opening is a result of roof collapse caused by marine erosion combined with the chemical weathering of limestone.
The name 'Algar de Benagil' refers to the sinkhole structure typical of the karst landscape in this region.
The cave is part of a larger network of sea caves spanning the coastline between Portimão and Albufeira.
The interior beach is tidal, meaning the sandy area shrinks significantly or disappears entirely during high tide.
The cave's formation highlights the porous nature of the Miocene limestone that makes up the Algarve coastline.
Benagil Cave is a natural sea cave located on the Algarve coast, defined by a large circular hole in its ceiling known as an 'algar'. The cave features two internal natural arches and a sandy interior beach accessible only from the sea. It is formed from limestone cliffs subject to intense erosion by the Atlantic Ocean. The cave is situated approximately 150 meters from the shoreline of Benagil Beach. Access is limited to authorized boat tours, kayaks, or stand-up paddleboards. Swimming directly into the cave from the main beach is prohibited due to strong currents and heavy boat traffic. The site is a protected geological formation within the Lagoa municipality.
From the water looking up through the 'eye' (the hole in the ceiling) at the sky.
Book boat tours well in advance as daily capacity is strictly regulated to protect the environment.
Check tide tables before visiting; low tide provides the most space on the interior sandbank.
Use a waterproof bag for cameras and electronics if arriving via kayak or paddleboard.
Attempting to swim from the beach to the cave, as currents are deceptive and dangerous; relying on unauthorized, non-certified tour operators.
Tours are subject to cancellation based on sea conditions and wind levels; access may be restricted during periods of high surf.
Do not attempt to climb the cave walls or touch the rock formations to prevent erosion. Swim with extreme caution due to boat traffic.
