The mountains of Sapanca are covered with forests while other areas are full of fruit gardens. The county and its surrounding is one of the greenest regions of Turkey. When you go to the southern part, to Samanlı Mountains, the forest cover gets thicker. The forest begins where Yanık River meets the lake; it extends over Sakarya River in the east, Mühlipınar River in the south.
Surface area of the county is 140 km2, the 10,543 hectares of forest covers 65% of the area of the county. In the mountains of Sapanca; there are mostly beech trees in the higher parts while there are also hornbeam, pine, mahogany, oak, linden, as well as chestnut and poplar.