Neptune's Grotto, Sardinia, Italy

Down 654 steps, perched perilously over the sea in Sardinia, Italy, you'll find a surprise waiting for you. Neptune's Grotto is a stunning stalactite cave that sits just over 3 feet above sea level. First discovered by local fishermen in the 18th century, the grotto was named after the Roman god of the sea. The entire cave complex stretches on for around 2.5 miles, although visitors can only access about 1,000 feet of the total. Inside, there's a labyrinth of lit pathways winding past stalactite and stalagmite formations, leading to a 390-foot-long saltwater lake.
Neptune's Grotto is near the town of Alghero on the northwest coast of Sardinia, the second largest island in the Mediterranean. It has been inhabited for at least 10,000 years, but its most important ancient civilization, the Nuragic peoples, lived there from around 1800 BCE until the 2nd century CE. At this time, villages were built around nuraghes, a kind of round tower fortress. Today, there are still around 7,000 of these nuraghes across the island, and they have become a symbol of Sardinia. Beyond its history, Sardinia is known for its pristine beaches, its rugged mountains, and its delightful cuisine.
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