End of historic US highway 566

Note: since I don't have access to a comprehensive collection of historical road atlases, much of the info below is based on the research of Robert Droz; click here to view his site. Photo credits: James Allen; Mark Roberts

Since their inception in 1926, all but one of the US routes in New Mexico has had its designation changed at least once (the exception is US 54). Originally, US 70 followed the route of today's US 60 across the state. The route heading southwest from Clovis through Roswell and Alamogordo (today's US 70) was US 366 [I]. The route serving the Roswell - Socorro corridor was designated US 566 because of its connection to US 366. The east end of US 566 was in Hondo NM, which is about 50 miles west of Roswell. The photo below is looking westbound on US 70/US 380 in Hondo:

Allen, May 2001

There was no US 380 in 1926, and US 70 didn't run through here. Rather, this would've been westbound US 366, which continued via modern US 70 to the left. The east beginning of US 566 was to the right.

US 566 went west from there, through Carrizozo, and ended at its junction with US 85 in San Antonio NM. The photo below is looking east on US 380; the I-25 interchange is not far behind the camera:

Roberts, May 2004

Today's NM hwy. 1 was originally US 85, so the west beginning of US 566 was straight ahead.

The map of the US highway system in these parts was drastically redrawn in 1932. US 70 was rerouted such that it ran through Clovis to El Paso. That change, along with a westward extension of US 60, rendered superfluous the US 366 [I] designation. A new US route was created, running east from Roswell into Texas. This route could've been considered an eastward extension of US 566, but instead the entire thing was designated US 380. It was an appropriate change, because this highway no longer connected with another route in the x66 family. So the west beginning of US 566 (above) became the west beginning of US 380. That remained the case for about 30 years, until I-25 was built through the state.