As we drive from Ljubljana towards the sea, we have no idea how many interesting things are hidden by the karst landscape. One of these features is the Planina plain, in the karst basin of the Ljubljanica river, and one of the treasures of karst phenomena. The Planina plain is a world-famous example of an ideal karst plain - a completely closed basin surrounded by the fascinating ruins of the Haasberg castle, the Planinska gora hill (with the pilgrim age Church of the Mother of God), the Lanski vrh hill, the Laški ravnik hills... To the south the water flows from under the ground - from Planina cave, Malni and during floodss even from the Škratovka cave... They join to form the Unica, whose meanders create a picturesque landscape. On the northern edge of the plain the river flows out of the dolomite on to the very soft limestone chalk and disappears. When it floods the ground is unable to swallow all the water, the Unica overflows its banks and pours over the flowering meadows, where the crowns of the trees are reflected off of the smooth surface of the newly formed lake.