Flatberget rises above the landscape at the eastern edge of the Sotunki valley as a central part of the village landscape of Sotunki city district in East Vantaa. The top of Flatberget has extensive open rock formations, the highest point of which reaches a height of 58 metres above sea level.
The Flatberget rock plateau is part of the Sotunki wilderness ridge. Old pine trees more than a century old grow around the rock's crown areas. Lower down, the vegetation changes to spruce-dominated borea…l forest. In lower hills, the vegetation resembles that of groves. There is a small swamp with subshrub vegetation in the northeast part of the region. In addition to that, two small spruce swamp depressions bring life to the swamp nature of Flatberget.
Flatberget has an extensive range of bird species. The species nesting in the area include many indicator species of an old forest, such as northern goshawk.
Flatberget became a protected area in 2002. The size of the protected area was around 30 hectares. In 2011, the area became part of the recently established Sipoonkorpi National Park.
The Flatberget region has unmarked pathways, and the area can be accessed via Tasakalliontie, for example.