[blam]

" Sea level rise would have put those cultural remains under water, for the most part, at the bottom of drowned river valleys (now tidal estuaries) and on the Continental shelf."

I've read that the Nile Valley leading into the ocean would have looked like the Grand Canyon during the Ice Age.

[Smokin' Joe]

The Chesapeake and Potomac estuaries would likely have looked similar. If I get time, maybe I’ll poke around Lake Agassiz’ shorelines on Google Earth. There should be something in the vicinity, there. If I could find the Ancestral Yellowstone/Missouri channel, there might be something palimpsest by the last glaciation there, but chances are anything would have been obliterated. You never know, and you can’t find it if you don’t look.