The Bory Tucholskie Biosphere Reserve is located in the Kuyavian-Pomeranian and Pomeranian Voivodships. It is the largest Polish biosphere reserve (area of 3,195 km²) and was established in 2010 by the UNESCO International Coordinating Council as part of the "Man and Biosphere" programme. The reserve is divided into three zones: core, buffer and transit zones. It aims to protect biodiversity as well as to enable better observation of ecological changes on a planet-wide scale.