Red Lake (Imotski) โ€” doline
Peter1936F ยท CC BY-SA 4.0

Red Lake (Imotski)

Crveno jezero

  • Elevation522 m
  • 2 min read
  • 43.455ยฐ N 17.198ยฐ E

Interesting facts

  • In May 2017 the French cave diver Frรฉdรฉric Swierczynski became the first person to reach the lake bed, touching bottom at about 245 metres in a four-hour dive.
  • The water level can swing by as much as 83 metres between seasons, yet it is the only one of the Imotski field's seven lakes that never runs dry.
  • A 1998 international cave-diving expedition measured a drop of more than 520 metres from the highest point of the rim to the floor of the lake.
  • Because the shaft is so hard to reach, the first depth soundings were taken only in 1955, by Milivoj Petrik.
  • About 15 metres below the surface an opening leads into a branching cave system with air-filled chambers, explored for some 800 metres, which also opens in the cliff above.
  • Much of the western wall collapsed in the magnitude 6.2 earthquake that struck near Imotski on 29 December 1942.
  • The Imotski spined loach shares the lake with the spotted minnow, and both fish have been found at every depth from the surface to the bottom.
  • Botanists have recorded 149 species of vascular plants on the walls, 15 of them legally protected in Croatia, with wild figs and grapevines just above the high-water line.
  • Nose-horned vipers and Balkan whip snakes hunt along the rock ledges, while greater horseshoe bats roost in caves in the cliffs.
  • The lake has been protected as a geomorphological nature monument since 1964.

Why it is worth it

The Red Lake is not so much a lake as a hole in the earth with water at the bottom. It fills a vast collapse sinkhole on the edge of Imotski in inland Dalmatia, where the roof of an enormous cave gave way and left a shaft with sheer walls. From the rim the cliffs drop more than 240 metres to the water, and the lake itself is deeper still, on the order of 250 to 290 metres, so that its floor lies a few metres below sea level. Measured from rim to bottom, it is counted among the largest sinkholes in the world and is the deepest known collapse doline holding a lake.

The name comes from the cliffs, stained a rusty red-brown by iron oxides. Looking down from the edge, the walls are pocked with caves and overhangs, and the water far below is a small, still disc that seems impossibly remote. Water leaves the basin through underground channels below the lake floor, and divers exploring the depths have found a large inflow passage, roughly 30 by 30 metres, opening into the eastern side at a depth of about 175 metres.

The lake is home to rare endemic fish, among them the spotted minnow Delminichthys adspersus, which occasionally turns up in springs and streams around the Imotski field in the dry season, a clue to hidden connections through the karst. The site is protected as a geomorphological nature monument and forms part of the Biokovoโ€“Imotski Lakes UNESCO Global Geopark, together with its neighbour, the Blue Lake, about a kilometre away.

Local tradition explains the chasm with a moral tale: a rich and miserly man named Gavan and his wife refused food and water to a beggar who was in fact an angel, and the ground opened and swallowed their house, leaving the abyss that is there today. Scientists since the late nineteenth century, from Philipp Ballif and Artur Gavazzi onward, have preferred cave collapse, but standing on the rim it is easy to see why the legend has lasted.

Getting there

The lake lies on the outskirts of Imotski, a short walk of about a kilometre from the Blue Lake. Split is about 100 km away by road, roughly an hour and a quarter's drive, and Split Airport (SPU) is the practical gateway. Mostar across the border in Bosnia and Herzegovina is about 50 km away as the crow flies; the nearer Braฤ Airport (BWK) is on an island and not a practical approach.

On these lists

The Most Beautiful Places in Split-Dalmatia 6The Most Beautiful Places in Croatia 22The Most Spectacular Sinkholes 14The Most Beautiful Natural Wonders 580

From the encyclopaedia

Red Lake is a sinkhole containing a karst lake near the city of Imotski, Croatia. It is known for its numerous caves and high cliffs, reaching over 241 metres (791ย ft) above normal water level and continuing below the water level. The total explored depth of this sinkhole is approximately 530 metres (1,740ย ft) with a volume of roughly 25โ€“30 million cubic metres, thus it is the third largest sinkhole in the world, and the deepest known case of a collapse doline containing a lake. Water drains out of the basin through underground waterways that descend below the level of the lake floor. The deepest known point of the lake is 4 metres (13ย ft) below sea level.

Wikipedia ยท CC BY-SA 4.0

43.45500, 17.19833per Wikidata