Well, we have some pretty trees, etc. on the CC Trail from C-470 South. Haven't finished turning yet, but I get some spectacular pictures each year.

Also, the Highline Canal is loaded with poplars - 1,000s of them, which can be quite spectacular, plus other foliage. Again, not sure if the have turned yet, but they are close. This is an easy ride for either mtn, cross or roadie - especially if you have 700x25 or larger. I do it all the time on a roadie.

Start at Writers Vista Park (Mineral west of Broadway a couple of miles on the south side) and you can go for miles and miles and miles. If you get to Colorado, you need to take a little detour before you get to Hampden. Head up Colorado on the street and go across Hampden, and pick the trail up again north of Hampden on the east side. This is because they do not let folks on the trail on Wellshire Golf Course.