Did you know that the trail hike with the greatest elevation gain in all of America lies only a hundred miles from San Diego? The starting point is the west end of Ramon Road in the city of Palm Springs, elevation 560 feet. The top, only 14 trail-miles away, is 10,804-foot San Jacinto Peak. That works out to be greater than 10,000 feet of net elevation gain! Yours truly has done the climb in seven and one-half hours, and that was after considerable training at high altitudes. Others have gone considerably faster. Most hikers in tip-top shape clock in at around nine to ten hours, assuming they have enough strength to reach the peak at all.
You begin with a mile-long ascent on the well-worn Carl Lykken Trail, then continue up a lesser trail going up a ridge trending southeast. That lesser route was originally constructed by the Civilian Conservation Corps in the 1930s. By the time the Palm Springs Aerial Tramway commenced operation in the '60s, the trail was virtually abandoned and forgotten. However, Palm Springs hikers began to take an interest in the trail some 15 years ago, and their efforts (plus the footprints of hundreds, if not thousands of hikers yearly) have made the route easier and easier to follow ever since.
Today the trail is variously known as the Skyline Trail, Sunrise Trail, Chino Canyon Trail, Cactus-to-Clouds Trail, and Outlaw Trail -- "outlaw" referring to the fact that rangers don't particularly enjoy rescuing exhausted or unprepared hikers on the route and don't particularly encourage its use.
After more than 8 miles of ascent, the Skyline Trail tops out in Long Valley (elevation 8400 feet) at a point about one-third of a mile south of the mountain tram station. Most hikers at this point simply throw in the towel, pull into the tram station for refreshments, and then take the next tram down the hill. Those wishing to continue to the 10,804-foot summit of San Jacinto Peak face an additional 12 miles of travel (round trip) on a wide, well-graded, popular trail (a free wilderness permit is necessary for this and can be obtained at the ranger hut below the tram station).
April-May and October-November are the only two reasonable periods each year for attempting the cactus-to-clouds climb. Summers are hellishly hot in Palm Springs, and the higher elevations of San Jacinto are snowbound in winter. After a wet, cold winter or spring, the uppermost part of the Skyline Trail just below Long Valley can be extremely hazardous due to lingering snow and ice. In a dry year the snow disappears by March; in a wet year there might be some remaining in May.
In the warmer months of May or October you may need to take a gallon of water on the ascent to Long Valley. The earlier you start, the better -- 4 a.m. in the springtime is ideal because you can experience temperatures in the 60s and 70s for nearly the entire ascent to Long Valley.