Berounka
The Berounka is a river in the Czech Republic, a left tributary of the Vltava River. It flows through the Plzeň and Central Bohemian regions to Prague. It is formed by the confluence of the Mže and Radbuza rivers in Plzeň. Together with the Mže, which is its main source, the Berounka is long, which makes it the fifth longest river in the Czech Republic. Without the Mže, it is long.
Etymology
The river is named after the town of Beroun. Originally, the entire stream was called Mže and the name first appeared in the 12th century, among others in Chronica Boemorum. The name was written as Mse, Msa and Misa. From the 17th century, the lower course started to be named Berounka, but the name Mže still appeared as a name for the entire stream at the end of the 19th century. In order to avoid confusion, an initiative to rename the lower course back to the historical name Mže was created in 2008, but its efforts were unsuccessful due to the strongly adopted current name.Characteristic
From a water management point of view, the Berounka and Mže are two different rivers with separate numbering of river kilometres. In a broader point of view, the Berounka originates in the territory of Mähring in the Upper Palatine Forest at an elevation of and flows to Prague-Lahovice, where it enters the Vltava River at an elevation of. It is long, of which is in Germany. In the Czech Republic, it is long, which makes it the fifth longest river in the country. Its drainage basin has an area of. The name Berounka is used from the confluence of the Mže with the Radbuza in Plzeň and from this point to the confluence with the Vltava, the river is long.The Berounka has many significant tributaries. The sources and longest tributaries of the Berounka are:
| Tributary | Length | River km | Side |
| Radbuza | 109.7 | 138.9 | right |
| Mže | 105.1 | 138.9 | – |
| Střela | 101.7 | 102.7 | left |
| Úslava | 96.3 | 136.0 | right |
| Loděnice | 64.7 | 30.6 | left |
| Litavka | 54.9 | 34.3 | right |
| Klabava | 51.2 | 121.9 | right |
| Rakovnický potok | 48.5 | 62.4 | left |
| Třemošná | 43.7 | 111.4 | left |
| Javornice | 30.9 | 81.3 | left |
| Zbirožský potok | 28.8 | 77.3 | right |
| Radotínský potok | 22.9 | 3.7 | left |
| Klíčava | 22.3 | 53.8 | left |
| Radnický potok | 18.7 | 96.2 | right |