US 77 (Denton, TX) was once Business US 77

[Brian556]

This is the only instance that I know of where a highway was bypassed, the old route became the business route, but returned to it's original designation.

I-35E/I-35 was completed around Denton in 1959. Maps created afterward identify the old highway through town as the business route. A sign photo in a 1970 newspaper proves it was signed Business 77. Sometime after, it somehow lost it's Business designation. I haven't pinned down when. It suspect it had to do with the removal of US 77 cosigning on I-35/I-35E sometime after 1977. I use that date because a newspaper pic from that year proves it was still co-signed at that time. I also believe the reason this wasn't signed Business I-35 is that one end intersects I-35 and the other end intersects I-35E.

[agentsteel53]

a related example:

I believe US-40 in Ohio was, at one point, routed onto I-70 with the old route being OH-440.  Then it was restored when people got used to "70" being the number of the primary through route.

[TheStranger]

This is the only instance that I know of where a highway was bypassed, the old route became the business route, but returned to it's original designation.

While not quite the same situation, US 117 was moved to the freeway that became I-795 in North Carolina a while back, but then moved back to what was Alt US 117 about a year ago.

[Alps]

Only one that comes readily to mind, Business US 70 (or US 70B) through Little Rock is once again US 70.

[TheStranger]

I do remember one that had escaped my mind when I first saw this post:

Originally, the Henry Watterson Expressway (I-264) was built as a US 60 bypass around Louisville (though the expressway is now within city limits after the 2003 city-county merger with Jefferson County).

Into the 1980s, it was signed as US 60/I-264, with the routing into downtown Louisville becoming Business US 60.  The mainline however was restored some time in that decade to the original surface street routing.

Don't know if there's any evidence of the 264/60 concurrency left on the Watterson.

[yakra]

TXDOT on US77 history...
...and 77Bus.

Another related example: Freeport ME had a US1 Business that became US1 Proper again a few years after the bypass route had I-95 overlaid onto it. [Floodgap Roadgap]