The Els Freus Marine Reserve covers more than 13,000 hectares between the islands of Ibiza and Formentera. Its waters hide natural secrets of the greatest importance, such as the world's largest and oldest living creatures: a Posidonia oceanica seaweed plant with an age of more than 100,000 years and an area of about 700 km2 that starts in Formentera (Es Feus) and ends in Ibiza (Ses Salines). It is an endemic plant species of the Mediterranean, and has been declared a World Heritage site by UNESCO. In spring the sea turtles cross here, which begin their long journey on the shores of Mexico. To see them is an experience as there is no second.

Formentera is known for being one of the best preserved sites of the Mediterranean. The clear view - depending on the season between 15 and 50 meters - and the great variety of the submarines landscapes make Formentera a perfect place for divers and also for snorkeling in crystal clear water with a constant temperature all year round. This makes diving one of the biggest attractions on the island. The variety of underwater landscapes caves and canyons provide the rest.