The lake is named for the reddish-brown color of the surrounding iron-oxide stained cliffs.
It is a cryptodepression, meaning the lake's bottom is below sea level while the surface is above it.
The water is almost impossible to access from the rim due to the sheer vertical walls.
The endemic fish species Delminichthys adspersus is uniquely found in the cave systems of the Imotski region.
The sinkhole's volume changes dramatically during periods of heavy rain, causing the water level to rise by dozens of meters.
Divers have attempted to map the bottom, but the extreme depth and narrow cave openings present significant technical challenges.
Red Lake (Crveno jezero) is a deep karst sinkhole located near Imotski, Croatia, containing a lake of significant depth. The sinkhole was formed by the collapse of an underground cave system, resulting in vertical cliffs reaching heights of up to 250 meters above the water level. The total depth of the sinkhole from the rim to the deepest point of the lakebed is approximately 530 meters, making it one of the deepest dolines in the world. The water level fluctuates significantly based on seasonal rainfall and groundwater infiltration. The lake is home to the endemic fish species Delminichthys adspersus, which has adapted to the unique subterranean environment. Scientific expeditions have utilized deep-sea submersibles to map the underwater cave passages connected to the lake. The area is geologically active and remains a site of ongoing speleological research.
The designated viewing platform along the rim, which provides the most stable and comprehensive view of the entire sinkhole.
Bring high-quality binoculars to view the water level and potential wildlife from the rim.
Wear sturdy hiking shoes with good grip if you plan to walk along the narrow trails near the edge.
Stay behind the safety barriers as the terrain around the rim is loose and prone to landslides.
Do not attempt to climb down the cliffs to reach the water level; it is extremely dangerous and strictly prohibited.
Maintain silence to respect the natural habitat; do not throw rocks or objects into the sinkhole, as it damages the sensitive ecosystem.
