What is the longest river in the Czech Republic?

The longest river in the Czech Republic is the Vltava.

The Vltava is about 431 kilometres long when measured from the source of the Teplá Vltava, its longer headstream, to its confluence with the Elbe at Mělník. It flows through Český Krumlov and České Budějovice before reaching Prague, where it passes beneath the city’s many historic bridges.

The river drains more than 28,000 square kilometres, covering over half of Bohemia and roughly a third of the Czech Republic. It is often called the Czech national river, and the composer Bedřich Smetana famously depicted it in “Vltava,” part of his symphonic cycle Má vlast.

The main confusion involves the Elbe. The Elbe is longer overall and continues through Germany, but within Czech territory the Vltava is the longer river. Hydrologically, the Vltava also carries more water at their confluence, even though the combined downstream river retains the Elbe’s historical name.