Maze Park is an urban nature reserve situated on the south bank of the Tees on former railway marshalling yards, the resulting landscaped mounds have been planted up with a variety of broad-leaved species. The other major habitat found on the site is rough grassland, which is managed for butterflies of which over 12 species have been recorded. The site's proximity to the river Tees provides good opportunities to see some of the river's Common Seals and the returning Salmon, which spawn in the river's upper reaches.