Ljubljanica Sluice Gate, Sluice gate and triumphal arch at Ljubljanica River, Slovenia.

The Ljubljanica Sluice Gate spans the river in three reinforced-concrete sections, each 2.4 m wide, with two 12.25 m overflow bays closed by pairs of roller and sliding gates. The piers are clad in stone and carry columns: Doric capitals with Etruscan vessels carved with dragon heads on one side, Ionic capitals with stylised human heads supporting the footbridge on the other. The weir crest sits at 281.41 m above sea level.

The structure was designed in 1939 by architect Jože Plečnik and built between 1940 and 1943 under contractor Matko Curk's direction. It emerged as an innovative solution for urban water control during a period of major city development.

Locals call it the Partition (Pregrada), and its three towers hide the sluice mechanism while carrying a footbridge. The columns are carved with dragon heads on the Doric side and stylised human heads on the Ionic side, details Plečnik used to give a waterworks the look of a temple.

The gate spans the Ljubljanica between Cukrarna and Vraz Square, downstream of Ambrož Square and upstream of the new Fabiani Bridge. It was planned as a footbridge, so pedestrians can cross the walkway linking the three towers. The sluice mechanism is housed inside the towers.

Plečnik also planned a river harbour and a small power plant for the nearby hospital beside the gate, but neither was built. The three towers that hide the gate mechanism rest on massive piers, and the structure is sometimes called a triumphal arch.