The Horse Spring is the best preserved of the three mineral springs located in the valley of the Chotěnovský Stream, which is the left tributary of the Kosí Stream. The name is derived from the rumours about a horse army that drowned in the near swamp during the Thirty Years War. According to other sources, the correct name of mineral water is the Chotěnovský or the Údolní Spring.
Since 1996 the natural mineral water spring in the alder forest, which is growing on a former meadow, is a protected natural monument. Interesting might be the size of the protected area – a four square meters. The spring is captured in an about half a meter deep hollow trunk. It is covered by a wooden shelter and connected with the forest road by a short boardwalk.
The spring is located on a slope on the western foothills of Teplá Highlands. Along the slope occurs an important tectonic line, the Mariánské Lázně Fault, which is also considered to be a major supply route of juvenile CO2. Increased magnesium content in the Horse Spring suggests that the geological environment in the area consists of basic rocks, namely of the Mariánské Lázně Metabasite Complex amphibolites.
Cadastre: Chotěnov
Composition type: not determined
Temperature (°C): 8
Capture diameter (cm): 60
Capture type: hollow trunk
Depth (cm): 70
Content of CO2 (mg/l): 2200
Sea level (m n. m.): 572