Strict nature reserves of Finland
Strict nature reserves (luonnonpuisto) are specific areas on state-owned lands in Finland which have been established by law for scientific reasons. Their primary purpose is the conservation of nature and research and "are to be permanently preserved undisturbed in as close to their natural state as possible." The regulations for the nature reserves are much stricter than those for the national parks of Finland.
Source: Wikipedia — Strict nature reserves of Finland (CC BY-SA 4.0)