According to the Guiness World Records:
"On 28 November 1996 Blue Water Recoveries Ltd (UK) discovered the wreck of the SS Rio Grande, using side-scanning sonar, at the bottom of the South Atlantic Ocean. On 30 November 1996 the find was confirmed by the company using a remotely-operated vehicle. The wreck, a World War II German blocade runner, lies at a depth of 5,762 m (18,904 ft)."