Olvassuo Mires. 02/02/04; Oulu; 27,073 ha; 65°07'N 027°15'E. Natura 2000 SPA, SCI, Finnish Mire and Esker Conservation Programmes, Strict Nature Reserve and Mire Protection Area. The site represents the mire vegetation region of southern aapa mires as a coherent and extensive area. Sedge fens with flarks and Sphagnum papillosum sedge fens are the most common mire types with nutrient levels varying from raised bogs to rich fens. Alluvial river shores are characterized by meadowy poor fens and spruce mires. Thirteen lakes with several ponds are situated beside the mires, and representative esker formations, wooded dunes and ancient shore banks give variety to the landscape. Most of the coniferous forests are old-growth and dominated by pine. The flora hosts some strongly threatened vascular plants such as Early Marsh-orchid, Narrow-leaved Marsh-orchid and Marsh Saxifrage. About 25 bird species of the EU Birds Directive Annex I breed in the area. Restoration of mire areas was carried out under the EU Life project in 1996-99 by filling ditches and cutting trees. In the Strict Nature Reserve visiting is prohibited except for local residents and for purposes of scientific research and education. Ramsar site no. 1524. Most recent RIS information: 2005.