Oldest BGS still standing

[jbnv]

If it has an outline of Louisiana on it, it's a candidate for the oldest in Louisiana. This one on LA 1 south of Natchitoches was still up as of May 2018.

[US 89]

Utah's oldest by far were these two button copy pull-throughs on I-15 at exit 59 in Cedar City. Unfortunately, both were replaced sometime between 2009 and 2011. This pair on I-80 would have been a great candidate as well, but they were removed in 2017. Almost everything good in this state has been replaced within the past 10 years.

Now...it's really hard to say, other than that it's probably on one of the freeways in Salt Lake that opened in the mid-1980s. At the rate UDOT replaces signs I can't keep track of what's still up and what's been replaced. One particular contender may be this sign, given its location on a 1985 freeway segment and lack of an exit number.

[stevashe]

I think there was still a black BGS on I-5 up around the Newhall Pass until about a decade ago, if memory serves.

Until sometime between January and June 2017 actually, according to google streetview: https://goo.gl/maps/CW2ik7AgdCMXD2aV6

I'd imagine both those signs are the same age? (Autos and Truck Route) Maybe it was black b/c it was a TRUCK ROUTE? It doesn't look like black from like the 1950s era signs.

Yeah that may be the case, especially since the replacement sign is white.

[PHLBOS]

For Massachusetts, now that the Clarendon Street on ramp to I-90 has been closed, the oldest BGSes still in place are the button copy signs on Route 33 in Chicopee and South Hadley.

I'm guessing that those are from either the late 60s or very early 1970s (no later than 1971).  That MA 33 shield is likely not original.  Back then, MassDPW typically used beige, rectangular route shields regardless of the number of digits a route number had.  Those style shields didn't age too well reflectivity-wise and dirtied very easily to a point where the shields looked brown over time.

Once these signs are replaced, the oldest ones (sans the route shields) will be the surviving 1972-vintage signs at both ends of MA 49 in Sturbridge & Spencer.  Next in line will be the 1973-vintage 3/4-mile advance sign for Old Sturbridge Village Rd. along US 20 westbound just beyond the I-84 interchange.

[Mergingtraffic]

For Massachusetts, now that the Clarendon Street on ramp to I-90 has been closed, the oldest BGSes still in place are the button copy signs on Route 33 in Chicopee and South Hadley.

I'm guessing that those are from either the late 60s or very early 1970s (no later than 1971).  That MA 33 shield is likely not original.  Back then, MassDPW typically used beige, rectangular route shields regardless of the number of digits a route number had.  Those style shields didn't age too well reflectivity-wise and dirtied very easily to a point where the shields looked brown over time.

Once these signs are replaced, the oldest ones (sans the route shields) will be the surviving 1972-vintage signs at both ends of MA 49 in Sturbridge & Spencer.  Next in line will be the 1973-vintage 3/4-mile advance sign for Old Sturbridge Village Rd. along US 20 westbound just beyond the I-84 interchange.

You have this on the US-5 connector and aren't there still 2 signs on US-6 in Fairhaven?

and


Fairhaven

[Mergingtraffic]

For Maryland I'd nominate:


For this one there's a pic somewhere online of showing this gantry as new from the 1960s.

[PHLBOS]

You have this on the US-5 connector and aren't there still 2 signs on US-6 in Fairhaven?

If that BGS indeed dates back to when the connector extended to I-91 circa 1969-1971*, then yes.  *best guess based on available historic aerials & topo maps.  Note, that replacement I-90 shield likely dates back to the 1980s.

and

I believe that one is 1980s vintage; given the reflectorized green background.

Fairhaven

Possibly, given that the US 6 shield once appeared to be beige when new.  Although the MassDPW was using beige shields on their signs until 1974.