1970 Interstate proposals

[Avalanchez71]

I recall drawing some of these same routes in my old atlases from my childhood! Those included the extension of the East Coast Interstate from New York to Georgia (only the Delaware part is shown there), the Rooftop Highway, and the one running up the western part of the Michigan mitt. However, I would not have guessed that before they settled on US 220 for a new Interstate corridor, they once considered US 421 from Greensboro to Wilmington via Fayetteville as a potential addition. But US 74 I definitely remember.

I preferred seeing the under construction lines stay that way and not get filled in.  I liked seeing US 66 in places and I-40 in the other places.  There is still little enough traffic in spots so that it still be viable today.  There is no need for interstates tearing up the countryside all over the place.  Why a rooftop route?