I'm thinking of places like New Orleans. The original city was built on a river bluff but then it expanded into the river bottoms. You have that phenomenon all along major rivers, towns expanding from upland settlements onto agricultural areas that are 100-year floodplains.

Of course, when the inevitable flood comes and everything is under water the urge to rebuild is stronger than accepting reason and settling elsewhere, also because money is missing, especially for the flooded-out people.