As you probably know, the Pacific Crest Trail (PCT) runs from Mexico to Canada. I am recommending a short segment that provides a mellow hike which wanders through the trees, with intermittent openings providing views across the Truckee River Basin all the way to Nevada. I am also recommending a longer, more strenuous hike along the spine of the Sierra Nevada that will be carpeted in wild flowers most of the year.
There are three trail heads. The most northern is reached by getting off I80 at the Boreal exit and taking the south frontage road to the end, where it enters a parking lot. The trail head is at the east end of the lot. The middle is reached from Donner Pass Road (Old Hwy 40). If you are going north, park on the north shoulder, just west of the pass. If you are going south, take the overused paved road just west of the Sugar Bowl Academy. Just after it makes a sharp right turn, there are parking places. Do not park right at the trail head or on the Sugar Bowl lot. The south trailhead is in Squaw Valley, off of Hwy 89, between Truckee and Tahoe City. Park in the main ski lot, then walk north on Squaw Peak Road to the Shirley Lake Trail head.
The first hike is a half day out and back trip between I-80 and Old 40 (Donner Pass Road). It can be done in either direction. It is about 2.5 miles each way, rolling mild to moderate difficulty. You are undulating between 7,000 and 7,200 feet during this trip. See northern segment PDF map.
The second hike between Old 40 and Squaw Valley is best done as a shuttle trip. It is 17 miles long, rolling and mostly moderate, with some more strenuous segments. Doing the hike going from north to south you gain 2,500 feet and lose 4,100 feet. See middle and southern segment PDF maps.
Starting from the north trail head, you follow a connecting trail east. A short way in there is a loop trail on your left that goes to a rest stop; ignore it. Pass some small ponds and glacially polished granite expanses, with some great views of Castle Peak to the north. About 1/4 mile in you hit the main trail where you turn south and climb gently to the top of a ridge. If you feel like a side trip, follow the ridge to the east where you can get great views of Donner Lake, Schallenberger ridge (named after a teen aged member of the Stephens party left behind for the winter) and the Carson Range. You can also see the Transcontinental Railroad on the right and I-80 on the left. The trail then trends downward and undulates through wooded terrain and between mountain tarns. About 2 miles into the hike when you start to climb, you can see on your left the rounded granite knob of Stephens Peak, named after the leader of the first successful trip over this pass in 1844. In 1846 the Donner Party made a wrong decision just about every chance it got, and its notoriety prevented Stephens from having the pass named after him.
You climb up the north shoulder of Stephens Peak, then drop down into a fairly level area. In a short time you come to a series of steep granite faces which are covered in climbers most of the summer (see "Donner Pass Climbing Areas"). A short distance after that, the trail hits Old 40 across from the Sugar Bowl Academy.
The longer hike begins at the middle trail head described above. It is located on the left just where the road makes the sharp right turn.
You start out in the headwaters of Summit Creek, which flows down into Donner Lake. Initially you are in a verdant riparian area which is full of alpine lilies at the right time of the year, then you quickly start switch backing across a steep granite talus slope. In a few hundred yards the trail begins to level off and you can look to the west to look down on Lake Mary and out toward Van Norden Meadows - a lush wetland which is the source of the Yuba River (see photo). It was also where Native Americans camped and traded during the summer. The trail then contours along the side of Mt. Judah, much of it in a beautiful red fir forest. This part of the trail is also part of the Mt. Judah loop, described elsewhere on the website.
Shortly after you leave the side of Mt. Judah, you come to a saddle where a side trail leads east to an overlook at Roller Pass (see photo). This is where travelers on the Emigrant Trail unhooked their oxen and led them up to the top, unloaded their wagons, took them apart, and then hauled them up the cliff over log rollers. Looking down into the distant valley and contemplating what they did is daunting indeed.
As you continue along the trail you sidle by Mt. Lincoln immediately to the west. You then come to a sharp ridge with Coldstream Canyon to the east and the Royal Gorge of the American River to the west. The meadow on this ridge is a solid carpet of wildflowers in the spring, as is much of the rest of the trip. The trail undulates along the top of the ridge until you reach Anderson Peak where the Sierra Club's Benson hut nestles in an indentation in the east face. The trail turns to the west and circles the peak before turning south again. Intrepid souls can take a short cut over the top of the peak (an easy climb) and then drop down to pick up the trail as it circles around. Be sure and check out the map first.
The trail continues along the crest and passes under Tinker's Knob (Knob is 19th century slang for nose). It jogs west to drop off the crest before turning south to contour a little lower along the ridge. It follows along the west edge of a plateau containing Mountain Meadow Lake, a pleasant, but shallow lake well on its way to becoming a meadow.
About 1/4 mile after the Mountain Meadow Lake trail the Granite Chief trail intersects the PCT. Here you turn east and begin to descend, initially through pine forest then over sheets of granite, and then over volcanic ash, all on the north side of Shirley Canyon. After a couple of miles, the trail crosses over to the south side of the canyon where it joins the Shirley Lake trail. Turn left and follow it out to the trail head behind Squaw Valley Lodge, and take the road to the left of the Lodge to the main Squaw Valley parking lot.
Starting from Squaw Valley you pick up the Shirley Lake trail behind Squaw Valley Lodge. This served as a dormitory for the athletes in the 1960 Olympics (a dormitory, how quaint!) After climbing about 1/2 mile, the sharply defined Granite Chief trail comes in at a sharp right angle just before a stream crossing. Follow it up to the PCT.
If, after traveling south, you are not tired enough when you get to the Granite Chief trail, you can continue on the PCT under Granite Chief peak until you can see Squaw Valley ski resort.
Turn east and work your way down among the lifts to Mountain Home Road on the south side of the valley. This will lead you to the Squaw Valley Village and the main parking lot. Do not go down into Shirley Canyon, unless you want a lot more walking. If you take this option, you will have covered 20 miles.