The Grand Canal of Nebida takes its name from the small valley of the Rio Grande Canal, which flows into the sea. "Channel" in fact, means campidanese channel, long valley. It is a cove that opens into the coast Iglesias, among Planusartu and Buggerru, with high walls that, in the south side, 115 m. On the north side, under the Punta Cubedda, is the Cave of the sea bass: an amazing optical effect given by the erosion of the sea on the metalliferous limestone. The shape of the cave favors the inclination of the rock layers of the cliff (that develops in 151 m and a height of 30 m). The bay ends in the valley known as the Rio Grand Canal, where you will find a trail of miners.
The area is also known for hosting one of the most important fossil localities of Cambrian inf. Sardo, in fact, coming here from beautiful specimens of trilobites, arthropods that lived in the sea floor about 550 million years ago.