Hranice Abyss - World's Deepest Freshwater Cave

Measurements are not over

Despite numerous attempts, the exact depth of this flooded cave near the Zbrašov Aragonite Caves remains elusive.

The quest to measure the Hranice Abyss's depth dates back centuries, with initial explorations occurring in 1900 and its depiction on maps as early as 1627. From using plumb bobs to divers delving into its depths in the 1860s, the first probe was sent into the cave in 1974, reaching a depth of 175 meters.

In 2016, the Hranice Abyss claimed the title of the deepest flooded abyss or cave when scientists lowered a robot to a depth of 404 meters, surpassing the previous record held by Italy's Pozzo del Merro.

The unflooded part of the abyss measures 69.5 meters in depth.

Hidden Treasures

The Hranice Abyss also hides the Dry Rotunda, a cave above the water's surface. Divers exploring the depths below the pool have captured stunning images of stalactite decorations, including the geyser stalactites resembling volcanoes with craters.

The Hranice Karst, encompassing the abyss, is truly unique. Unlike most karst formations, which result from surface water erosion, this particular formation was shaped by powerful outpourings of thermal mineral springs from the depths.

Mysterious legends

Shrouded in a dark atmosphere, the Hranice Abyss has inspired many legends. One of them suggests that the abyss formed at the spot where a knight from the nearby Svrčov Castle and his young wife, a widow from the fortress in nearby Ústí, in their wedding carriage plunged into the ground - perhaps to hell, as it is said that the knight had murdered the landowner out of lustful desire.

According to another legend, the Moravian King Mojmir II jumped into the abyss on horseback, only to have his pursuers, among the treacherous grandees threatening Moravia, do the same in the darkness of night.

Records from the 16th century describe the Hranice Abyss as "some kind of hell into which people condemned to death used to be thrown," suggesting it may have served as an execution site during the Middle Ages.

How to get to the Hranice Abyss

To reach the Hranice Abyss, located in the Hůrka National Nature Reserve near Hranice, you can enjoy a pleasant walk from the spa town of Teplice nad Bečvou. Once there, you'll be treated to a magnificent view extending as far as Hostýn or the Beskydy Mountains.