Union Bay Natural Area, or Union Bay Marsh, is the restored remnant of former marshlands at the east end of the University of Washington campus in Seattle. Once reshaped by the lowering of Lake Washington, the opening of the Montlake Cut in 1916, and decades of dumping and landfill use from 1911 to 1966, the site survives as the main open remnant of a much altered bay edge. Today it contains shoreline, marsh, woods, prairie patches, and ponds that support abundant urban wildlife, including more than 150 bird species. Continued restoration, including work tied to Ravenna Creek, has made it a refuge and a visible example of landfill converted into wetland habitat.