The Promontory Park boat ramp is located in Oregon and is a concrete ramp that provides access to the waters of Detroit Lake. The ramp is approximately 20 feet wide, allowing for easy launching and retrieval of boats. The coordinates of the ramp are latitude 45.22413254 and longitude -122.24645233.

According to the latest information available, the ramp is open year-round, and motorized boats are allowed on Detroit Lake. However, there may be certain restrictions and regulations on the type of craft that are permitted on the water, as set forth by the Oregon State Marine Board.

The waters of Detroit Lake are popular for a variety of recreational activities, including fishing, water skiing, and pleasure boating. Visitors to Promontory Park can also enjoy swimming, picnicking, and camping in the surrounding area.

Overall, the Promontory Park boat ramp is a well-maintained facility that offers convenient access to the beautiful waters of Detroit Lake in Oregon.