At the 6 mile mark there is a huge Dam on the right - this is where most people turn around. This is also the start of the Colorado Trail. The road gets steep here and after another 1/2 mile or so, turns into singletrack. It's a steep switchbacky climb through the woods - but it's not too long. Several years ago when I used to do a bit of racing I was doing this as a training ride - well, some guy passed me on the climb wearing cut off jeans, tube socks pulled way up and riding a hoop-dee WalMart bike - I heard him coming up fast and, without looking, I pulled over to let him motor through. I thought: "What the.....?"
I caught him later on the climb - but only because he had stopped to smoke a cigarrette.
Anyway, the trail tops out in a saddle where there is a homemade bench dedicated to some dude named Lenny. If you keep going strait you'll end up in Durango (in about a week)......or take the trail to the left and climb a bit more and you will eventually circle back around and end up back at the dam. This left hand option includes probably the best 2 mile stretch of singletrack around - swoopy banked corners, water crossings - super fun......and since everybody does this loop the same counterclock wise direction - you can let it go without much chance of meeting somebody coming from the opposite direction. Last week when I was running this stretch I found a really nice CO2/mini pump combo that somebody had dropped. The person that dropped it was probably having such a good time on this downhill he probably said "screw it" and kept riding. I'm serious, they could charge admission for this section.
You'll eventually drop down through a technical section and back onto the gravel road, right near the dam - back into that hot-ass canyon.
Only 6 miles of headwind to go back to the car where (if you were smart) you have that cooler full of cervezas. Ride total: about 17 miles