The Truckee River Canyon between Truckee and Tahoe City features a string of camp grounds and picnic areas. Various biking and hiking trails can be accessed from within the canyon. Other trails, such as the Sawtooth Trail, skirt the canyon and provide scenic vista points. Most prominent, the Western States Trail, which in major sections coincidences with the nation's first non-motorized, coast-to-coast American Discovery Trail (ADT) , crosses the canyon.
Getting to the Western States Trail crossing and the TRT
The Western States Trails crosses the Truckee River on a Highway 89 bridge half-way between the Squaw Valley and the Alpine Meadows turnoffs. Driving south, you may find right-side shoulder parking before or after this bridge, overpassing the Truckee river and bike trail. Parking space is very limited. Just before driving onto the bridge, you'll see the Western States Trail signpost to your right. From the south end of the bridge, the Truckee Bike Trail can be accessed. Underpass the bridge on the bike trail and immediately ascend to find yourself on the opposite side of Highway 89. Here, the eastbound Western State Trail starts as a single-track trail. The trail winds out of the canyon for about two miles through pine and fir forest. Turn left at its junction with the TRT. Good luck with the painted rocks!
References and more to discover
 American Discovery Trail: California [www.discoverytrail.org/states/california/ca_info.html].
 trailhiker: Western States Trail - Painted Rock loop from CA-89 [trailhiker.wordpress.com/2012/09/18/western-states-trail-painted-rock-loop-from-ca-89/]