I never fail to visit this Las Sirenas Reef when I go to Cabo de Gata. Its in the town of Cabo de Gata and is by a long straight road that goes to the left next to the salt fields. At the end you will find a small lone church - depending on what time of day it is it may seem "sinister". From there, continue up a narrow road (with very steep curves) which leads to the Cape. Here you will find a viewpoint where you can see sharp coral rocks jutting out from the sea.