Sep 26, 2020 · The largest ship ever built was an oil tanker; the Knock Nevis built in 1979 (launched as the Seawise Giant) with 565,000 dwt, a length 458 meters, a beam of 69 meters, and a draught of 25 meters. The ship was so large that no port could accommodate it fully laden, so it was loaded and unloaded while anchored offshore