This trail drops down into the basin and you can either climb back out, or connect to the Arizona trail. The Arizona trail will take you out to Reddington Pass, at which point you have to take the dirt road back into town. Taking the AZ trail requires parking one car at the bottom of the road to Reddington Pass and shuttling to Mt Lemmon. I think the total ride distance is close to 20 miles if you go out Reddington Pass.
Take the Mount Lemmon Highway to Molino Basin (mile 5.6). Park at the Molino Basin campground parking lot. The trailhead is across Mt Lemmon Hwy from the parking lot.
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