Located by the sea, they are named after the sea seal in the Sardinian language. The Bue Marino Caves are located in the centre-west of Sardinia, in the municipality of Dorgali. Sea water and fresh water from the interior have formed communicating tunnels 20 kilometres long, divided into three branches. Only one is currently open to the public, the southern branch.
Here it is possible to walk along a scenic one-kilometre walkway, for a stretch along the seashore. In the future, the parts that can be visited will increase thanks to the research of cave divers from all over the world. It was discovered that the Grotta del Bue Marino communicates with those of Su Molente, Monte Longos and Su Palu, raising to 70 the number of kilometres theoretically accessible. The ticket costs 12€ but is well worth it.