Lacul Rosu Harghita

Lacul Roșu, also known by its Hungarian name Gyilkos-tó (the Killer Lake) or, in an older form, Lacul Ghilcoș, is a natural dam lake situated in the Munții Hășmașul Mare, part of the Eastern Carpathians, at an altitude of approximately 983 metres, near the locality of Lacu Roșu and Cheile Bicazului, in Harghita County. The lake formed in 1837 (the exact date being disputed among specialists), following the collapse of a mass of earth from the north-western slope of Muntele Ghilcoș. The landslide, triggered by heavy torrential rain and possibly by seismic activity, blocked the valley into which the streams Verescheu (Roșu), Licaș, Suhard and Valea Oii drain, causing water to accumulate. The lake has a surface area of approximately 12 hectares and a maximum depth of around 10.5 metres; its shape is reminiscent of the letter "L", with two main arms. Its name derives from the reddish colour the water sometimes takes on, caused by iron oxides and hydroxides carried from the eroded soils of the surrounding slopes by Pârâul Roșu. The Hungarian and German name (Mördersee, meaning "the Killer Lake") is linked to a local legend according to which the landslide buried a shepherd along with his flock. The lake's most distinctive visual feature is the trunks of fir and spruce trees, remnants of the forest that was flooded when the lake formed, which are partially petrified and remain visible above the water to this day, giving the landscape a spectacular and slightly sombre appearance. The lake was officially given the name "Lacul Roșu" in 1936. The area forms part of the Cheile Bicazului-Hășmaș National Park, a protected natural area of exceptional importance, which entails restrictions on human activities. The resort of Lacu Roșu has developed around the lake and serves as a starting point for numerous mountain trails towards Cheile Bicazului, the peaks of Suhardului and Muntele Ucigaș.