Modro Jezero – Blue Lake

Modro Jezero (Croatia) from above. Seen the road built for the visit of Emperor Frantz Joseph I
Modro Jezero from above. Seen the road built for the visit of Emperor Frantz Joseph I / Wikimedia Commons, user Modzzak, CC BY-SA 3.0
One of the most beautiful and interesting karst formations in Dinaric Alps is Modro Jezero – approximately 220 – 290 m deep sinkhole with beautiful lake on its bottom and vertical cliffs around it.

General description

Most likely this sinkhole formed after the collapse of enormous cave hall. Not far from this sinkhole are other large sinkholes including one of the largest in the world – Crveno Jezero.

Upper opening of the sinkhole is approximately 520 m long and 280 m wide, 290 m deep. Volume – 22 million m³. The sinkhole has very steep sides – southern rim is vertical. For the most part at the bottom of the sinkhole is a lake. Lake level is up to 342 m above the sea level (at high water).

The lake is the most interesting feature of the sinkhole. This beautiful blue-green lake, in general, is 800 x 500 m large. The level of this lake varies with the season and rainfall. In spring it can be up to 100 m deep but in summer – even totally dry with mud-filled holes in locations where the water disappeared.

Modro Jezero in Croatia. Note the person below, at the forefront. There are seen also traces of much higher water levels
Modro Jezero. Note the person below, at the forefront. There are seen also traces of much higher water levels
/ Wikimedia Commons, user Dreizung, CC BY-SA 3.0

In 1914 the lake rose up to 114 m depth and started to flow over the southern rim of sinkhole.

Earlier the lake was deeper – but an earthquake in 1942 caused large landfall and thus reduced the depth of lake.

Upper rim of surrounding cliffs rises some 220 m above the bottom of sinkhole.

The intermittent level of the lake has formed several caves around it – Boškova, Golubova, Top, Vilinska. Boškova cave is hard to reach – it was used as a shelter during World War II.

Exotic swimming place

The lake of this sinkhole is easy to access and thus it is a popular swimming place.

A road with breathtaking sights was built to the lake for the visit of Emperor Franz Joseph I in 1907. Since then the road has been repaired many times and is very busy in the summertime. At high water level, the lower end of this road is under the water.

In the lake there are seen several notable boulders, which in a way serve for easy determination of the lake level: Katavić, Jakićin, Pavić. When the 6 m tall Katavić appears, the swimming season may start. Name of Jakićin is given to commemorate a man who drowned here in 1834 – this boulder marks the middle of the swimming season. Pavić appears at the end of swimming season.

Towering above the lake there is a vertical cliff, where swimmers are jumping in the lake – some even from 40 m height.

When the lake dries out, the flat bottom is used even for playing football – between the local teams Vilenjaci and Vukodlaci.

Above the lake is towering ancient fortress – Imotski Fortress (Topana) – mentioned in written sources already in the 10th century, built around 845 – 864 AD. Imotski town developed around this fortification.


  1. Modro Jezero. Accessed on August 13, 2010

Modro Jezero on the map

Travelers' Map is loading...
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Location, GPS coordinates: 43.4501 N 17.2107 E
Categories: Sinkholes, Lakes and streams
Values: Geology, Visual
Rating: 3 out of 5 stars (3 / 5)
Where is located? Europe, Croatia, Split-Dalmatia, some 24 km north-east from Makarska, 0.4 km north-west from Imotski
Alternate names: Blue Lake, Plavo jezero
Depth: 290 m, lake up to 90 m deep

Video of Modro Jezero

01Portal, May 2019

Landmarks of Croatia

Plitvice Lakes in Croatia
Plitvice Lakes in Croatia / Bart Dubelaar, / SA BY-SA 2.0
The natural and cultural heritage of Croatia is diverse and very charming. Highlights of Croatia are the ancient, beautiful Dalmatian seaside cities and towns and the diverse karst formations – such as waterfalls with tuff formations, sinkholes, caves and others.


Great Blue Hole, Belize
Great Blue Hole / Eric Pheterson, / CC BY 2.0
Category includes outstanding sinkholes – large natural depressions or holes, which for most part represent collapsed caves.

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