Yeah, but that massive surge of water can be astoundingly "tall", too.
I mean, in the Japan tsunami, there were tall (not skyscraper, but multi-story office towers) buildings that barely managed to have their roof un-swept in some places.
Definitely the most terrifying natural disaster in terms of sheer scale, barring mega-volcanoes or massive asteroids and whatnot that'd just, you know, wreck global civilization.