Description: This data set contains polygon features of existing environmental corridors and isolated natural resource areas for the seven county Southeastern Wisconsin Region. The polygon features were delineated on land use inventory maps, with reference to 1"=400' scale aerial photographs, and digitized from these source materials. The data set was collected at 5-year intervals, and is current for the years 1990, 1995, and 2000. The polygons consist of primary and secondary environmental corridor areas and isolated natural resource areas as defined by the Southeastern Wisconsin Regional Planning Commission (SEWRPC).