The allure of the Illes Medes, seven islets off L'Estartit beach, lies in their range of depths (down to 50m), kaleidoscopic marine life, and underwater cavities and tunnels. Since being gazetted as a reserva natural submarina in 1983, this archipelago has seen marine species thrive, making it Spain's most popular destination for snorkellers and divers. As of 2010, the islets form part of the protected 80-sq-km Parc Natural del Montgrí, les Illes Medes i el Baix Ter.
On and around rocks near the surface are colourful algae and sponges, as well as octopuses, crabs and various fish. Below 10m to 15m, cavities and caves harbour lobsters, scorpion fish and groupers. With luck, you’ll spot some huge wrasse. If you get down to the sea floor, you may see thornback rays or marbled electric rays. Bottlenose dolphins make appearances too.