One of the two massive ships, built by Roman Emperor Caligula, that were uncovered in Lake Nemi in the 1920s.
Under orders from Mussolini, the lake was drained and the ships were dug out. However, the two ships were destroyed in World War II.

These large Roman vessels were floating palaces built in the 1st century at Lake Nemi.

https://rarehistoricalphotos.com/caligula-nemi-ships-1932/ - https://www.discovermagazine.com/planet-earth/nemi-ships-how-caligulas-floating-pleasure-palaces-were-found-and-lost-again - https://commons.wikimedia.org/wiki/File:Nemi-Schiff.jpg and
https://penelope.uchicago.edu/~grout/encyclopaedia_romana/miscellanea/nemi/nemi.html