A dive on the Montgri coast some 15 minutes sail from the port of L´Estartit. Here we find a little island very close to the coast from which we moor in order to do the dive. A tunnel crosses the island from one side to the other. Its entrance is at 18 metres and the exit at 24 metres, with an overall length of 70 metres. Its inside is very wide and high, with an open roof in many places that allows the sunlight to pierce through, making it very special. Before we arrive at the exit we find a wide chimney that rises from 22 metres to 12 metres. Within its walls and ceiling we can find red coral, lobsters, and fauna typical of tunnels. We do not have to enter the tunnel if we do not want to. Instead we could do a beautiful dive around the island, where if we look closely we can find an infinity of small marine life.