Some stations in Prague were at 200 cm/s, according to some sources [0] before EU regulations cut it to a maximum of 90 cm/s (TFA puts Prague at 65 cm/s today, and you know, I'm not on a Prague escalator right now, so I suppose I'll trust them).

I can't find a better source for just how fast the Prague escalators were, but as an occasional user they seemed more than twice as fast as London or Paris which TFA gives as 65-75 cm/s.

They felt dangerous to step onto, but I never saw anyone actually have an accident. The metro in Prague is also deeper than most.

[0] https://www.expats.cz/czech-news/article/prague-s-speedy-len...