Karolina Spring, Mineral spring in Mariánské Lázně, Czech Republic

Karolina Spring is a mineral spring in Mariánské Lázně whose water has a calcium-to-magnesium ratio of 2:5. It rises in Skalníkovy Sady by Reitenbergova Street and is piped to the colonnade shared with Rudolf's Spring, at the end of the promenade from Křížový pramen, beneath the Church of the Assumption.

The spring was discovered in 1809 and was originally called Nový (New). In 1817 it was renamed in honour of Caroline Augusta, wife of Emperor Francis I, not a queen. A circular pavilion with a dome and eight Corinthian columns, often attributed to Josef Esch, was built over it in 1811.

Originally called Nový pramen (New Spring), it was renamed in 1817 in honour of Caroline Augusta, wife of Emperor Franz I of Austria. The spring is housed in the cast-iron neo-baroque colonnade shared with the Rudolf Spring, built in the Blansko ironworks, where visitors drink from two taps side by side.

The spring is accessible throughout the year and located within easy walking distance of most hotels and accommodations in town. It is best to visit in the morning when fewer people are present and the water tastes particularly fresh.

The calcium-to-magnesium ratio here is 2:5, an unusually magnesium-rich balance that underpins its use for kidney stones and urological complaints. The spring was originally called Nový (New) and received its present name in 1817, honouring Empress Caroline Augusta, wife of Emperor Francis I.