Build in 1952 as USS 483, a MSO AM Class Ocean Minesweeper. To the Dutch Navy as part of the Mutual Defence Assistance Program" (MDAP) in 1954.
January 17th, 1955, USS 483 received the name "Hr. Ms. Onverschrokken" and hull number M886. Renumbered on April 5th, 1972, as A856 (Auxiliary ship)and rebuild as "Torpedo Trial Tender".New name was given as Hr. Ms. Mercuur.
Out of service February 1987, since april 1993 in use as a floating museum.
Update 11-01-2016: At this moment, the ship is not longer present in Scheveningen and is the future unknown. For more information, please read the press release of the Stichting Behoud Maritieme Monumenten (Dutch Only) ;
www.museumschip-mercuur.nl/ 