Ljubljanica, River of Seven Names
The unique river of Slovenia
The river that rolls lazily through Ljubljana, the capital city of Slovenija, is named Ljubljanica when it surfaces on Ljubljansko Barje (Ljubljana Marshes) near Vrhnika, and it keeps that name until it merges with the river Sava. It is thought that the river has been named for the city of Ljubljana, but it was known as Ljubija in Middle Ages, which means that the city might have been named for it. The extent of the variously named watercourses over the full length of the river is impossible to determine. A major part of the river before it emerges as Ljubljanica, flows through the mysterious Karst underground of Rakov Škocjan, reappearing on the surface near the town Vrhnika. It flows over Cerkniško polje and Ljubljansko barje, finally weaving its picturesque way through Ljubljana and on to its confluence with the river Sava, for the whole length of about 41 km.
If we move along the current to its source, the river Ljubljanica is first named Unica, then follows Pivka (western branch) surfacing in Zagorje in Pivka Valley, Rak (eastern branch) flowing through Škocjan Caves Regional Park, continuing in the streams Stržen, Obrh and Trbuhovica. And so the river is poetically said to have seven names. Establishing its beginnings, does not by any means resolve the issue of its source. This is a karst region, where waters tend to flow underground, emerging on the surface in different places. So far karstologists have been unsuccessful in trying to establish the source among the many sinkholes (Sl. ponor) that feed the river Ljubljanica in the final part of its course.
Waters of the river Ljubljanica make their appearance at two fairly distant places. The right branch named Trbuhovica emerges on the surface across the Croatian border, the left branch makes an appearance on the other side of the mountain ranges, the mountains Snežnik and Javornik. On the right branch, the waters gradually flow from the edge of Babno polje towards the low-lying Loško polje, where again two great groups of streams develop, one as Mali Obrh near Vrhnika, the other as Veliki Obrh near the castle Snežnik. From Loško polje the waters flow towards the Cerkniško polje, as the stream Stržen. When this stream overflows, which occurs at least once a year, the famous intermittent Lake of Cerknica (Cerkniško jezero) makes its appearance.
When the waters of the intermittent lake have receded, the brook Cerknišnica meanders over Cerknica polje (Cerkniško polje). The water of the lake disappears in sinkholes, and resurfaces in the landslide gorge of Rakov Škocjan as the river Rak. It flows under two magnificent natural bridges and disappears into the cave Tkalca jama. It reappears in the cave Planinska Jama, where the left branch of the river Pivka joins it. This means that the two rivers, Rak and Pivka, uniquely merge underground in the cave Planinska jama.
Peter Skoberne, the author of the publication Ljubljanica od izvira do izliva (Eng. Ljubljanica from Source to Estuary) describes its course from the source in Zagorje and along the Pivka Valley, scenic with a number of intermittent lakes. In the great flood of 2000, they counted 17 lakes between Ilirska Bistrica and Postojna. Another peculiarity of the area is that the waters of Šembilje Lake flow into Adriatic Sea, while the others flow into the Black Sea. This is due to the ridgeline dividing the villages Bač and Šembilje. Here we may mention the lake Petelinje jezero, which is the habitat of the fairy shrimp (Lat. Chirocephalus croaticus), now found only here and nowhere else in the world. In autumn and spring water shoots up in geysers in some places, and brings to the surface the endemic karst creature proteus anginus ...(Sl. človeška ribica).
Near Postojna the river Nanoščica merges with river Pivka and together they thunder into the sinkhole of the famous karst cave Postonjska jama. The two branches of Ljubljanica, the rivers Rak and Pivka, finally merge in the cave Planinska jama, erupting into the light of day from a mighty rocky gateway and spilling out over the valley Planinsko polje as the meandering, and occasionally flooding river Unica. Eventually it vanishes from sight underground. When it re-emerges near Vrhnika, it is finally the river Ljubljanica. Flowing over the Marshes of Ljubljana (Ljubljansko Barje) it finally reaches the city for which it has been named, its course tamed by the urban planner architect Jože Plečnik. The river winds its picturesque way through the city, circling the Castle Hill and merges, together with the river Kamniška Bistrica into the river Sava. So we may speak of the merging of three rivers, Sava, Kamniška Bistrica and Ljubljanica.
Exploration of the karst river Ljubljanica.
Among the important explorers of the Karst region Janez Vajkard Valvasor (17th century) should be mentioned in particular. In his famous work The Glory of the Duchy of Carniola (1689) he was the first to describe in detail the functioning of the intermittent lake Cerkniško jezero. Two years earlier Valvasor sent a paper of 27 pages to the notable Royal Society of London, the main scientific institution of Europe at the time, and was consequently elected a Fellow of the Royal Society.
We may add here that according to experts, the mention of Luega Palics (marsh lake) by the Roman author Strabo is a reference to the lake Cerkniško jezero, although it may be also a reference to the marshes of Ljubljana, Ljubljansko Barje. Valvasor described many other connections between various parts of the river Ljubljanica, among other things he asserted that its waters have no relationship with the waters of the river Reka. He wrote that they are opposites, despite fraternal similarities and closeness, Ljubljanica flowing into the Black Sea, Reka, under the name Timava flowing into the Adriatic Sea.
Another significant explorer of the Slovenian Karst was the Czech Engineer Viljem Putick, known in connection with the cave Škocjanska jama. In 1886 he was sent by the Court in Vienna to Notranjska (Inner Carniola) to investigate the hydrology of Karst region, with the objective of preventing flooding. After two years of solid work he introduced several measures, however without noticeable result. Subsequently other scientists, speleologists, and cave divers explored and endeavoured to unravel the mystery of the complex underground water system of this region. It was only in 1975 that the hydrological puzzle was partly solved by the use of colours in the water currents.
In recent times Pavel Kunaver conducted an investigation into the phenomenon. It is to his credit, that no destructive interventions were attempted in the valley Planinsko polje and the intermittent lake Cerkniško jezero. The plans for a multi-purpose accumulation were already in place, but were fortunately never carried out. The planning for drying or flooding of these karst valleys continues. It is to be hoped that environmentalists will succeed in realizing their vision of a regional park. The Town Council of Cerknica has already declared the lake of Cerkniško jezero a natural heritage area, comprising the waterways, the plants and the animals, including the subterranean ones.
Ljubljanica, the river that had served for travel and transport of goods as far as Vrhnika at the time of Valvasor, flooded at times of seasonal rainfall, like other karst rivers. The architect Jože Plečnik had safeguarded the city from flooding with high embankments and a sluice gate. Significant steps were already taken in 1777, when Gabriel Gruber, was given the task of drying Barje, the marshes to the south of Ljubljana. His solution was the canal, now called Gruberjev Kanal, which carried off the excess water.
Today, Ljubljanica, the river of seven names, is still the wild mysterious river, flowing untamed until it reaches the city of its final name. There she becomes civilized and beautiful, flowing majestically through the city, between high embankments, beneath gracious bridges, and turning its overhanging branches from white to green to gold with the seasons. On its course around the brooding Castle Hill the river of Ljubljana, offers delightful vistas, charming promenades, enchanting sunlit cafes, and inviting resting places along its length.
BibliographyTranslated into English by Aleksandra Ceferin