The USS Knave (AM-256) was an Admirable class minesweeper built for the United States Navy during World War II. On October 2, 1962 the Knave was transferred to the Mexican Navy along with 17 other sister ships and commissioned as the ARM (Armade de Mexico) DM-13. The vessel was later renamed Cadete Juan Escutia (C-56). In October 2000 C-56 was scuttled by then Mexican president Ernesto Zedillo, a diver himself, to serve as an artificial reef and SCUBA dive site. The vessel rests upright, on a sandy bottom, in about 90 feet of water. For a detailed history of the ship’s operations during WWII visit C-56.
A nice Youtube video of a dive on the C-56.