History: 2 Guys sailing in the underground water cistern built by Emperor Justinian the Great. Constantinople, Ottoman Empire. Early 20th century.

https://i.redd.it/f94or0s84z971.jpg via /r/HistoryPorn https://www.reddit.com/r/HistoryPorn/comments/og5e5g/2_guys_sailing_in_the_underground_water_cistern/?utm_source=ifttt