Sail out into the western Caspian Sea and you’ll soon encounter an incredible sight: spires of steel rising from the waves, connected with miles of decrepit pipes and wooden bridges. This is Neft Dashlari, an inhabited, Soviet-era structure that’s said to be the “largest and oldest offshore oil city in the world.” It remains a productive source of petroleum to this day, as well as a token of interest to esoteric-architecture fans or parents wanting to punish bad children with the worst theme-park vacation ever.