CPV code 92533000 designates Nature reserve services in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
92533000 is a leaf code — the most specific level of its branch — so it can be used directly as the main CPV code of a contract notice. If it does not quite fit, check the neighbouring codes under 92530000 (Botanical and zoological garden services and nature reserve services).