State Route 366 - Swift Trail

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Arizona 366 travels from US 191 west through the Coronado National Forest up to the top of Mt. Graham and the Pinaleño mountain range. The road was added to the state highway system in 1961-62.

Arizona 366 is a winding road, with sharp curves and no guardrails. The road is quite scenic, but only paved for the first 21 miles (between miles 114 and 136). The last 7 miles are gravel, and are closed to vehicles from November 15 to April 15.

There are no reassurance markers on Eastbound Arizona 366.

Arizona 366 is designated as the Swift Trail Parkway scenic road. The road was designated as a scenic highway in 1993.

Arizona 366 west
Distance sign to Columbine Ranger Station (where the state highway ends) and Riggs Lake. Photo taken 11/11/07.
This is the first and only reassurance marker on Arizona 366 westbound. Photo taken 11/11/07.
Trucks above 40 feet are not recommended along Arizona 366. There is a truck turnaround just after this sign. Photo taken 11/11/07.
Arizona 366 is subject to daytime closures. This could be due to the Mt. Graham observatory located atop the mountain. Photo taken 11/11/07.
Arizona 366 travels around Cyclone Hill to enter Jacobson Canyon. Photo taken 11/11/07.
Arizona 366 is a winding, twisting highway as it climbs Mt. Graham. This is advance warning of the upcoming curves. Photo taken 11/11/07.
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Perspective of Arizona 366 as it begins it's rapid climb up Jacobson Canyon. Photos taken 11/11/07.
As the road heads further up the sky island, mature forests become more and more visible. Photo taken 11/11/07.
Arizona 366 features sharp curves with no guardrails, such as this one. Photo taken 11/11/07.
Tall trees are common on the "Sky Island" of Mt. Graham. Photo taken 11/11/07.
After reaching the 8500' tall Lady Bug Saddle, Arizona 366 levels out and follows the top of the mountain, with a much more gradual climb to the Ranger Station, where the road ends. Photo taken 11/11/07.
Arizona 366 east
There is a downhill grade all the way from Lady Bug Recreation Area (from 8300 feet down to 2900 feet in 19 miles). Photo taken 11/11/07.
Distance sign to U.S. Highway 191 and Safford. While the distance may be short, it's not a fast drive down the mountain. Photo taken 11/11/07.
The vistas along Arizona 366 face all the way down to Arizona 191. This is one of the places where Arizona's famed clear skies can be seen quite easily. Photo taken 11/11/07.
As Arizona 366 descends from Turkey Flat, these panoramas can be seen along Twilight Creek. Photo taken 11/11/07.
The bridge over Wet Canyon is a one lane stone bridge. Photo taken 11/11/07.
This bridge over Wet Canyon was constructed in 1936 by the CCC. Wet Canyon is a well-preserved riparian habitat, one of the few remaining in Arizona. Photo taken 11/11/07.
After crossing Wet Canyon, Arizona 366 enters the Jacobson Creek drainage. Photo taken 11/11/07.
While descending along the north side of the canyon, the vegetation gets less dense and more shrub-driven. Photo taken 11/11/07.
The panoramas towards the San Simon Valley are amazing from the descent of eastbound Arizona 366. Photo taken 11/11/07.
Beyond the final set of curves, Arizona 366 enters the broad alluvial fan as it descends towards U.S. 191. Photo taken 11/11/07.
Advance signage for U.S. 191, 1/2 mile. Photo taken 11/11/07.
Arizona 366 ends at U.S. 191. Turn left for U.S. 191 north to Safford, or right for U.S. 191 to Interstate 10. Photo taken 11/11/07.
There is no end shield for U.S. 191, just this sign denoting which direction to go to Safford or Willcox. Photo taken 11/11/07.

Photo Credits:

11/11/07 by Kevin Trinkle

Connect with:
U.S. 191

Page Updated 11-18-2007.