The Black Soil of Ljubljana Marshes and the Treasures Beneath

The vast Ljubljana Marshes, a 163 square kilometers of flat, marshy land south of Ljubljana, are a strangely beautiful place, rich in biodiversity, geology, prehistory and history.

The black soil of Ljubljana Marhses


The basin of the Marshes formed at the end of Lower Pleistocene (~800.000 years ago) by a collapse along two still active faults, the Vic fault in the north and the Podpec fault in the south. Around the Last Glacial Maximum (20.000-15.000 years ago) Sava river formed an alluvial fan that blocked the rivers and streams flowing from the south and west, creating a large, shallow lake. The sediments started to accumulate, slowly filling the lake up, and the depth of sediments today reach over 100 m.

Ižica river

When the lake started to dissapear, the people arrived to its banks and built unique settlements called pile-dwellings; basically platforms erected on stilts driven into the lake bed, with huts and houses on them, giving the inhabitants some protection against wild animals and other humans. The pile-dwelling remains date back to 3rd millenium BCE and are a part of the Pile Dwellings around the Alps UNESCO World Heritage Site. The oldest extant wooden wheel – over 5000 years old! – was found in the Marshes,

There were two pile-dwellings discovered in this area between Izica and Zelimeljscica rivers, the Rezman channel and Gornje Mostisce

The lake kept silting up and the people moved to the terra firma; the lake became a huge marsh. The soft, soggy wet, squishy soil prevented building of houses and even roads; the peat accumulated to over 6 m thick in places, marshy conditions ruled out any agriculture. The only activity in the Marshes was cutting up the peat, using it as a fuel.

Ižica river and the drainage channels

In 1780 the Gruber Canal was completed in order to prevent regular floodings of the Marshes; the water runoff was increased and groundwater table was lowered – this enabled the first serious try of drying up the Marshes and transforming them into an agriculural paradise.

Many drainage channels were dug since, the rivers and streams were straightened and deepened; roads were constructed, a couple of villages were established in the middle of previously inhospitable Marshes and first fields were sown.

However, a mash is a marsh. Soils formed in such wet conditions are not very fertile; while they can appear black, marshy soils are heavy, wet, poorly drained, and acidic. Gleysols – black, blue, and even greenish due to anoxic conditions – support limited crops, such as beets, cabbages, and corn. Regular floodings still affect large parts of Ljubljana Marshes, so corn that can withstand floodwater (the corncobs grow high enough on the stalks so the water can’t reach them) is a preferred crops of valiant Marsh farmers.

Life on Ljubljana Marshes is hard, but this unique landscape has so much to offer to a visitor; prehistoric pile dwellings, villages and farms, fascinating remains of once vast peat bogs, rare plants and animals, rivers and springs… The protected landscape park is just waiting for you to explore it – on foot, riding a bike, or flying a kite!

All kite aerial photos shot with Canon A810 on a dr.agon D90 BW mini delta.

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