A “paternoster” is an old-school elevator that consists of a chain of open compartments that moves slowly up and down in a loop. To get to the floor you need to get to, you hop in a compartment and, on reaching the required floor, you just hop off. To see what it's about, have a look at this video:
You cannot stop the elevator, you cannot call the elevator. This just goes and goes in an infinite loop. With the European Union energy label going from A to G, this would probably get... something like a W: this must be incredibly energy-inefficient, going 24-7, day and night. However, we really recommend hopping in when you're in Prague because... they're fun! We have put together a small map of these gems. You're welcome.
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