Embedded Files
100 years of US routes: 1926-2026
US route endpoint in
When the US routes were first commissioned in 1926, US 80 went through Douglas. However, no north-south US route served the town until 1938, which is when the US 666 designation was extended into Arizona:
c. 1938, Rand McNally
That lasted until 1992. At that time, US 191 was extended south all the way to Douglas, replacing what had been US 666. These photos were looking south on US 191 at its junction with AZ hwy. 80 (which is historic US 80):
Jensen, 2002
Field, May 2003
Elbert, Apr. 2008 (unchanged as of 2011)
Note that there was no reference to "Business 191" there (more on that below). According to ADoT route logs, that junction is where US 666 ended from 1938-1962, and again from 1971-1992. That is consistent with this USGS map, which showed US 666 ending in the upper left corner. Pan American Avenue was not yet a continuous road, so instead of using it (as AZ 80 does today) US 80 traffic was directed through the downtown area. The Mexico border crossing was not served by a signed route...
c. 1958, USGS
...or at least not a US route. However, the minutes from AASHO's June 1962 meeting indicate the US 666 designation was to be extended east with US 80, then south on what had been designated AZ hwy. 666:
That change must have coincided with the completion of Pan American. So from 1962-1971, US 666 ended at the Douglas port of entry. If a driver turns left (east) from US 191's current terminus, the road becomes 16th Street, where this overhead sign was posted:
Elbert, Apr. 2008
Hmm, so we are still on mainline US 191, and it continues to the right? Well, actually in about 2023 that US 191 shield was removed, and the ground-mounted assembly just ahead from there tells a slightly different story:
Elbert, Apr. 2008
Elbert, Mar. 2023
Oh, so it is actually Business 191. Not far to the right on Pan American is the border crossing:
Faye and Sandy, Mar. 2007
That was looking south on Pan American, past 3rd Street. That was the south end of US 666 from 1962-1971. From 1971-1992 it was the south end of Business 666, and since then it has been the south end of Business 191. If one were to turn around and head north from there, the first confirming assembly (at 3rd) has a Business tab...
Karners, Dec. 2011
...but when one gets back to 16th, the overhead signage once again made it look like we were on mainline US 191...
Faye and Sandy, Mar. 2007 (unchanged as of 2011)
...until 2023, when that sign too was replaced, and it now indicates that 16th is how one gets TO US 191:
Elbert, Mar. 2023
Heading the opposite direction (southbound Pan American at 16th) overhead signage also indicated a junction with mainline US 191 until it was changed in 2023:
Elbert, Apr. 2008
About a mile to the right (west), travelers come to this junction (shown here from both westbound and eastbound AZ 80):
Elbert, Apr. 2008
Field, May 2003
Karners, Dec. 2011
Drivers turning north from there will soon see the first confirming assembly for northbound US 191 (the sticker on the lower left -- gone as of 2011 -- said "Historic US 666"):
Elbert, Apr. 2008
According to ADoT records, US 191 officially ends west of town (where the "End" sign is posted). East from there is just AZ 80 to Pan American (which would explain why there is no signage for "Business Spur US 191" at the junction where mainline 191 ends). Business 191 runs from Pan American down to the border crossing... which is very unusual, because it does not intersect mainline 191 (Business 666 never touched its parent, either). Until 2023, east of that junction, there were actually more references to mainline 191 than there were to Business 191.
Research and/or image credits: Chris Elbert; Andy Field; Alan Hamilton; Jeff Jensen; Karin and Martin Karner; Dale Sanderson
Page originally created 2003;last updated May 13, 2025.
Page updated
Google Sites
Report abuse