Markham Prairie is the largest and highest quality prairie in Illinois and in large parts of adjacent states. As a mesic prairie intergrading between sand prairie and typical tall-grass prairie on loamy soil, it is a remnant of a distinct and formerly widespread biotic community type of the Central Lowlands biophysiographic province. The site is also an excellent example of undeveloped lakebed and beach ridge topography.
Year designated: 1987
Ownership: Federal, State, Private
Please remember, National Natural Landmarks (NNLs) are not national parks. NNLs are owned by a variety of public and private entities and allowing visitation is at their discretion. Many NNL sites maintain public websites where additional information may be found.