Take a serene bike ride on Lakeside's El Monte Road, and get a glimpse of San Diego County's rural past.

If you're a bicyclist with an antipathy for steep hills but a love for rural scenery, you'll appreciate El Monte Road. Few rural roads in San Diego County can offer as long a stretch of relatively flat terrain and relatively light traffic -- at least early in the morning.

El Monte Road follows the broad upper valley of the San Diego River, a place where springtime breezes blow almost invariably out of the west. This will assist your gradual uphill climb into the narrowing river valley and slow you down a bit on the return descent. Green wild grasses have been sprouting throughout the valley, and the chaparral vegetation on the hillsides is blooming as a result of the March rains. April promises to be the prettiest month of the year along this stretch.

From Lakeside's core area -- Maine Avenue or the nearby Lindo Lake County Park -- pedal east on Julian Avenue one mile to Lake Jennings Park Road. Straight across is El Monte Road, which descends briefly to the San Diego River valley floor and then very gradually ascends, staying close to the base of the hills on the south side. Scan these hillsides to find the horizontal trace of the old San Diego Flume, a 35.6-mile redwood marvel that shunted water from an upper tributary of the San Diego River into San Diego's municipal water system, starting in the late 1800s. The flume was abandoned following the construction of El Capitan dam in the 1930s. Some of the Depression-era houses hereabouts were cobbled together out of the flume's salvaged lumber.

Today, the river valley seems stuck in a time warp, resembling Santee and El Cajon some 50 years ago. Agriculture still thrives here, though less and less as time goes on. About five miles into your ride, you'll come to El Monte County Park, graced with some of the largest and finest coast live oak trees in the county. The park is open during daylight hours for picnicking.

On the road again, you resume the climb -- a bit steeper now. The sheer-granite south face of El Cajon Mountain, known as "El Capitan," looms above in Yosemite-like splendor. Two miles past the park you reach a gate, which is unlocked for vehicles Saturday through Monday. El Capitan Reservoir lies ahead, open for boating, fishing, and picnicking (though the water level has been quite low of late). Flatlanders should start their return at the gate; hillclimbers can tackle the remaining steep pitch that leads to the reservoir dam and the boating and fishing concession that lies beyond.