So Steven Universe question, 

why do so many gem structures seem completely untouched by humans or at least modern humans. Like they’re crumbling but just in a normal ruins way. Some of them are places humans couldn’t get to like that one underwater palace but most are perfectly above land and don’t seem to have anything stopping people from finding it. People have planes and helicopters and stuff so you’d think people would see things like the communication relay and be like “the fuck is this? Super stonehendge?” or the gem battlefeild “what the fuck is with all these giant strawberries and giant ass weapons” or the kindergarden “what the fuck is this horror manga shit”