Same but different, there's an old town near a lake that suffered a devastating flood way back in its history. The downtown area has markers on the buildings that show the high water mark for the flood.
That's what parent poster was referring to. They have high tide markers showing where tsunamis have reached, and then in the past 50-100 years people started saying "Waves Of Unusual Size? I don't think they exist" and building closer to the shoreline.