Limnigraph in Výtoň, Technical monument in Výtoň, Czech Republic.

The limnigraph in Výtoň is a square Art Nouveau building on the Rašín Embankment, designed as a romantic gloriole with a columned arcade along the embankment. Each of its four walls has a large circular water-level dial with a clock above it. A copper dome topped by a crown with a compass indicator and a dog-head weather vane covers the structure.

This structure was built before World War I as a meteorological station measuring atmospheric pressure, temperature, and water levels. From its inception, it focused on scientific monitoring of the river.

The name Výtoň refers to the toll point where raftsmen paid duties on timber floated down the Vltava. The wooden rafts were steered by boatmen called voraři, and the riverside district grew around this timber trade. The nearby Podskalská celnice, a customs house facing the limnigraph, recalls that river commerce.

You can observe the device from outside, viewing water level readings through markers on all four sides. The location sits directly on the riverbank, making visits during normal water conditions most informative.

The four clock faces on each side display both time and water measurements simultaneously. This design makes many passersby mistake it for an ordinary street clock and overlook its actual purpose as a scientific instrument.