The cave system was discovered in 1949 by explorers who found the original entrance, which had been blocked by a landslide.
The Alepotrypa cave within the complex contains a Neolithic burial site and served as a sanctuary during the late Stone Age.
The navigable portion of the underground river is one of the longest in the world accessible to tourists.
The internal temperature of the cave remains stable at approximately 16–20 degrees Celsius year-round.
Some sections of the cave walls are covered in white crystalline calcite, providing high light reflectivity.
The water level within the cave is directly influenced by the tide of the adjacent Diros Bay.
The Caves of Diros, specifically the Vlychada cave system, feature a subterranean river accessible primarily via small wooden boats operated by professional guides. Located in the Mani Peninsula, the cave contains a massive collection of stalactites and stalagmites formed over millions of years. The navigable route through the water spans approximately 1,200 meters, followed by a short walking path section. The cave is part of a larger complex that includes the Alepotrypa cave, which serves as a major archaeological site. Geological research indicates these caves were once dry land before rising sea levels submerged the lower levels. The constant internal temperature remains relatively cool throughout the year regardless of external weather. Excavations have revealed evidence of human habitation dating back to the Neolithic period, including tools and pottery. The water within the cave is brackish due to the proximity of the Mediterranean Sea.
The wide, chamber-like areas where the guide pauses the boat and the lighting highlights the reflections on the water surface.
Bring a light jacket as the humidity and temperature drop significantly inside the cavern.
Secure any loose belongings or cameras, as the boat transfer is tight and involves navigating low-ceiling sections.
Wear non-slip footwear to manage wet surfaces during the transition from boat to walking path.
Do not attempt to touch the stalactites or stalagmites; the oils from human skin permanently stop their growth.
Operations are significantly reduced or suspended during the winter months; the site typically closes for maintenance on Mondays during off-peak seasons.
Strictly no flash photography is permitted to protect the delicate cave formations and avoid disturbing the cave's ecosystem.
