Middle Mississippi River National Wildlife Refuge lies downstream from St. Louis on bottomland spanning Missouri and Illinois along the Mississippi River. Managed by the U.S. Fish and Wildlife Service within the Mark Twain National Wildlife Refuge Complex, it includes Meissner, Harlow, and Wilkinson islands. Nearly all of it is wetland, though these tracts were once diked riverine polders used for agriculture. Their modern history was transformed by the Great Flood of 1993, when breached dikes damaged the parcels and led to their transfer to the federal government. Established in May 2000, the refuge represents a deliberate effort to restore altered farmland to semi-natural bottomland habitat.