Do any true arcologies exist in the world?
An “arcology” is a science fiction premise of a small civilization living inside a single large building. Everyone there lives and works in the same building, and all services are provided within the building that everyone needs. That’s not to say the building is totally self-sufficient. Mail comes and goes. As do consumer products that residents order from beyond. But all services are provided such that there is no need to ever exit the building for any reason.
(Of course, you may go outside if you wish, but most science fiction scenarios present a situation where venturing outside the building is either dangerous, unhealthy, etc.)
Does anything like this really exist in the world (big cities like NYC where all or most buildings are interconnected via subway stations don’t count)?