Ascend Palomar Mountain the back way via the old Nate Harrison Grade

The 21st Century journey up Palomar Mountain is perhaps too easy, notwithstanding the nauseatingly curvy South Grade Road that leads expeditiously to the top. With extra time, you can always revert to an earlier and more bone-shaking route -- the 100-year-old Nate Harrison Grade. If you are physically fit, mountain biking up that road -- almost 4000 feet up in less than ten miles -- is a significant challenge. But no one will fault you if you wimp out by driving a car on it.

Originally a wagon track designed to accommodate one-horsepower engines of the animal kind, the road is now reasonably wide and well graded enough for all but low-slung cars with spongy suspensions. The grade is named after Nathan Harrison, a freed slave who homesteaded a small ranch part of the way up the incline. For many years, Nate graciously provided water for thirsty horses and travelers coming up the mountain.

From Highway 76 near Pauma Valley, follow Nate Harrison Grade as it runs upward along a sloping alluvial fan dotted with citrus orchards. The pavement soon runs out, and you start a twisting ascent of the mountain itself. Pauma is an Indian word meaning "place of little water," which is evident in the area's sparse native vegetation -- mostly white sage at this elevation. Relentless climbing on straights and switchbacks takes you to ever-higher vantage points. Downward glances encompass patchwork quilts of green and brown below and broadening views of North County and (if it is unusually clear) the ocean.

Eventually, the aromatic sage-scrub vegetation draping the lower mountainside gives way to oaks. Higher still, the oaks are joined by tall firs and cedars, and you reach the boundary of Palomar Mountain State Park. There you hit pavement again, enjoying the distinctly cooler breeze and the silky smooth feel of a road devoid of serious bumps.

If you want to make this a loop trip of about 30 miles, continue straight through the park and exit the park's main entrance on East Grade Road. Ahead another couple of miles is Palomar Mountain's main crossroads and tiny commercial center -- your opportunity to tank up on food and drink. From this point on (assuming you're biking) you can cash in on gravity's debt to you. There's almost 4400 feet of descent ahead, entirely on pavement, all the way back to Pauma Valley via South Grade Road and Highway 76. Watch your downhill speed -- some of the turns are sharper than they look and span more than 180 degrees of curvature.