I remember taking the escalators in Moscow in the 80s and thinking they were freakishly fast. According to this article they are not that fast. I wonder if they lowered the speed or it was just my lack of familiarity with long escalators.
The speed combined with the wind can be quite wild.
You might also enjoy this comparison with London:
The video also explains that escalator speed is now set via international standards.
Thank you.
The salient bit: The Prague escalators were made by the Soviets and ran at 0.9m/s (aka very fast) so it's likely the ones I rode in Moscow were similar. They are "illegal" now and being replaced.