One of the largest networks of underground caves in Italy is found 24 km from Alghero, in northwestern Sardinia. Neptune’s Grotto caves were discovered by fishermen in the 18th century. The original entrance is a meter above sea level and is accessible only at low tide. Entry has been gained from the cliff above, via 654 steps carved into the rock. Several chambers, such as the Great Organ, the Lace Room and the Music Stand, feature stalactites, stalagmites and rock column formations. At 9m below sea level there is a large underground lake with white sandy beaches. The site is also accessed by ferries from Alghero, which run hourly in season.

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