Nifty map which shows all the major “divides” in the continental U.S. There’s the main Pacific/Atlantic divide, but there’s also a north/south divide for water flow to the Arctic or the Gulf Of Mexico and secondary ones for Columbia/Colorado flow into the Pacific, etc.
Lots of fun geographic and road geek ephemera on that site. Photos and info on the endpoints of U.S. Highways, geographic features of the high plains, and a look at “Parting Of The Waters” a creek that flows into two oceans.