The Tower of London which houses the Crown Jewels [0] has a conveyor belt / moving walkway that you have to stand on to see some of the exhibits. It thus contro

The Tower of London which houses the Crown Jewels [0] has a conveyor belt / moving walkway that you have to stand on to see some of the exhibits. It thus controls access and limits the time you can spend in one of the rooms (I can't remember if it possible to get back to its start to go round again) [0] https://en.wikipedia.org/wiki/Crown_Jewels_of_the_United_Kingdom https://en.wikipedia.org/wiki/Crown_Jewels_of_the_United_Kin...