Mill Creek Park was established in 1891 by Volney Rogers as the first park district in Ohio. Mill Creek Park is the largest area of the MetroParks encompassing over 2,658 acres of the MetroParks' 5,000+ acres.

In the context of "Metroparks" (which are typically regional park systems serving a specific metropolitan area), the Huron-Clinton Metroparks in Michigan is one of the nation's premier systems, with Kensington Metropark serving as its high-value crown jewel at 4,481 acres. However, if looking at the largest "urban park" managed by a city/metro authority, Chugach State Park in Anchorage, Alaska, is the undisputed king at nearly 500,000 acres—the largest urban park in the world. For more traditional "Lower 48" city parks, South Mountain Park in Phoenix (16,000+ acres) and Franklin Mountains State Park in El Paso (24,000+ acres) are the highest-ranking "big" parks located entirely within municipal boundaries, providing vast desert and mountain escapes.