Minto-Brown Island Park is a large park in Salem, Oregon, adjacent to the Willamette River. The name can be somewhat misleading, as neither Minto Island or Brown Island are islands, but are instead part of a peninsula separated from the mainland by a slough. However, the area is a wetland, in a flood plain.
Minto-Brown Island Park is 1200 acres, or about two square miles, immediately adjoining downtown Salem. Most of it is kept as a nature park, with wildlife viewing, especially of wetland-related birds, as well as mammals, reptiles and amphibians, and insects. Although the park is mostly nature oriented, it has many miles of paved and unpaved trails, as well as some park facilities, as well as a dog park. While this makes access easier, it also probably discourages many of the more shy species of birds and mammals from frequenting the park.
Two square miles is not a gigantic park, but I managed to spend several hours walking around the park last summer, and only saw about half of it. Given the diversity of landscapes and habitats in the park, it is possible to spend a lot of time exploring meadows, wetlands and riverbanks, and a mile's walk can turn into hours of experience. It is also interesting to note that while the Willamette River has many different natural landscapes, and that Oregon is known for being environmentally conscious, between Eugene and Portland, there are much fewer places to access the river than might be guessed, especially in cities. Minto-Brown Island Park, while a fragmented natural experience, is still one of the largest, and richest places to experience the Willamette River close to an urban area.