For 5.2 miles Mountain Dell Canyon follows Clear Creek along SR-65 from Little Dell Reservoir to Big Mountain Pass. The canyon bottom is a lush riparian habitat dominated by cottonwood and other deciduous trees. The shrubsteppe and mixed oak covered hillsides line the canyon walls extending up into the hills on both sides. As you ascend past the Affleck Park Campground about 1/2 way to Big Mountain Pass, the road becomes windier with several switchbacks. The habitat also changes when large stands of Aspen become a dominant part of the south side of the canyon. Small patches of coniferous trees dot the landscape, while some cliff habitat joins the scenery on the north side. There is often some confusion with regards as to what Mountain Dell Canyon actually encompasses. The area has been referred to as East Canyon, Upper Emigration Canyon, and Mountain Dell Canyon in the past. Maps show Mountain Dell Canyon starting below Little Dell Reservoir, but don't specifically list a name for the area above the reservoir. Over time this name has fallen into place, and may or may not be geographically correct.
Mountain Dell Canyon is a beautiful short drive on the way to Big Mountain Pass. The birding isn't phenomenal, but it can be very good. There are a few very specific species that you will find on almost any trip birding here in the summer months. Both HERMIT and SWAINSON'S THRUSH can usually be heard at dusk, while YELLOW WARBLER is a common sight. Both GREEN-TAILED and SPOTTED TOWHEE are expected, and CHIPPING SPARROW are in no short supply. SONG and FOX SPARROW can usually be turned up while a colorful contingent of species are often encountered including: WESTERN TANAGER, BLACK-HEADED GROSBEAK, LAZULI BUNTING, and AMERICAN GOLDFINCH. Almost any trip here will produce that list of species, while with a little work you may turn up ORANGE-CROWNED and MACGILLIVRAY'S WARBLER--and even VIRGINIA'S. GRAY CATBIRD have been reported, as have AMERICAN DIPPER on the creek. DUSKY FLYCATCHER are occasionally encountered higher up, while RED-NAPED SAPSUCKER might be found in the aspen patches. The canyon is also particularly good for owling. FLAMMULATED OWL and NORTHERN SAW-WHET OWL can often be found in the summer months with some searching. GREAT HORNED and LONG-EARED OWL have both been observed as well. COMMON POORWILL can be heard at night, but are much harder to pick out. The road is closed from mid-November, usually till about May. It depends on how much snow is present. The canyon can often be a popular evening drive so it can be busy in the summer, but usually not too bad. It is a popular spot for bikers, and at night deer are often on the road coming to water, so be very careful on the windy road.
From I-80 exit 134 take SR-65 north for 2.9 miles past Little Dell Reservoir. Once you pass the reservoir you enter the canyon. It continues another 5.2 miles till you reach Big Mountain Pass.