Bisoca Lakes Nature Reserve

The Bisoca Lakes nature reserve is a mixed forestry, botanical and geological reserve of IUCN Category IV, covering 10 hectares, located to the north-west of the centre of the commune of Bisoca, on the Dealurile Ungureanului hills, at an altitude of approximately 900–950 m. The primary conservation feature is the Scots pine woodland — Pinus sylvestris — a species with a limited distribution in the sub-Carpathian zone of Muntenia, alongside specimens of black pine. Between the pines, successive communities of herbaceous species unfold, ranging from mesophilous to sub-thermophilous types. The reserve is also geologically significant: the lakes formed in sinkholes developed in sandstone, with beds of settled sedimentary mud. Originally there were four lakes — Lacul Limpede, Lacul Negru, Lacul Rotund and Lacul Sec — but the last two dried up as a result of surface erosion. Only two remain: Lacul Limpede, the only one to have survived silting, and Lacul Negru — named after the colour of its water, caused by abnormal eutrophication, located 200 m away and more than 70% covered by vegetation. Locally, Lacul Negru is also known as "Lacul fără Fund" ("The Bottomless Lake"). The forest shelters a natural amphitheatre with a stage built from stone and wood, where local folklore performances and activities take place, and there is also the possibility of accommodation in cabins just a few metres from the lake. The reserve is part of the UNESCO Geopark Ținutul Buzăului, recognised in 2022, and can be combined in the same day with Belvedere Bisoca and Cascada Bisoca, all three located in the commune of Bisoca.