Pramen Rusalka, Mineral spring in Karlovy Vary, Czech Republic

Pramen Rusalka is a mineral spring located within the Mill Colonnade in Karlovy Vary, discharging water at approximately 60 degrees Celsius. The spring sits within a historic covered gallery constructed in the late 18th century.

Known since the 16th century, the spring originally rose in the bed of the Teplá and was called Nový pramen. In 1746 it was captured in a pine-wood basin, later replaced by linden. A wooden promenade hall was built over it in 1792–1793, replaced in 1811 by Giessel's Empire-style colonnade and in 1871–1881 by Josef Zítek's Neo-Renaissance Mill Colonnade.

The spring's name Rusalka refers to a water nymph in Slavic folklore, a name it received after being known for centuries as Nový pramen (New Spring). It is freely accessible on the Mlýnská kolonáda, where visitors can drink from a spout. The spring emerges in the promenade hall alongside two other springs, Kníže Václav and Libuše.

The spring is located in the Mill Colonnade, easily accessible on foot from Karlovy Vary center or by local transport. The covered gallery provides shelter while you explore the warm water source at your own pace.

The spring rises in the promenade hall of the Mill Colonnade together with two other springs, Prince Wenceslas and Libuše, while the Mill and Rock springs have their own vase-shaped outlets on either side of the hall. Since 1984 it has been tapped by a bore 7.8 metres deep.