park units are now state forest campgrounds and another two units existed on state lands which were sold to private interests and closed. (The Former state park units section lists each of these former units.) Additional DNR facilities DNR operates 746 boat launches on of designated public water access sites. It also operates 16 "harbors of refuge" as well as providing support for the other 61 harbors in the system. The harbors of refuge are approximately apart along the Great Lakes shoreline to provide shelter from storms and often provide boat launches and supplies. There are 11 state underwater preserves covering of Great Lakes bottomland and ten of them have a maritime museum or interpretive center in a nearby coastal community. The DNR Parks and Recreation Division also manages 138 state forest campgrounds (including a dozen equestrian campgrounds). The Michigan state game and wildlife areas encompass more than . DNR also oversees the trail systems in the state. This includes of non-motorized trails, of rail-trails, of off-road vehicle (ORV) routes and of snowmobile trails. For a discussion of all protected areas in Michigan under all jurisdictions, see Protected areas of Michigan. Michigan state parks Michigan state recreation areas Michigan trail state parks The following state trails are units of the State Park System. Several other state trails fall under Department of Natural Resources jurisdiction and/or maintenance, but are not state park units and are not included here. Other sites Former state park units Benzie State Park – (1929–1975) donated to the National Park Service in 1975 and is now the Platte River Campground of Sleeping Bear Dunes National Lakeshore Bloomer State Park No. 1 – (1922–late 1960s) 36 acres, absorbed into Proud Lake State Recreation Area; now Bloomer Park in West Bloomfield Township Bloomer State Park No. 2 – (1922–1945) 50 acres, originally Dodge Brothers State Park No. 7; incorporated into Rochester-Utica State Recreation Area, now Bloomer Park in Rochester Hills Bloomer State Park No. 3 – (1922–1944) 100 acres, later incorporated into Ortonville State Recreation Area, northeast of Ortonville Bloomer State Park No. 4 – (1922–1947), 28 acres, now Bloomer Park in White Lake Township, undeveloped site sold as it was "not of state park calibre" with funds used to purchased additional lands for the new Rochester-Utica State Recreation Area Cheboygan State Park – (c.1921–1945) 15 acres, original state park located on the site of the current Cheboygan County