Take Interstate 125 in San Diego to Navajo Road. Turn right onto Navajo. Turn right at Cowles Mountain Road, then left onto Boulder Lake Ave. Turn right at Barker Way and look for the trailhead on your left.
The Barker Way (fire Road) route up Cowles Mountain is a quick, steep hike that is good training. For a less stressful hike, take the Barker Way trail instead of the Fire Road. This fork is clearly marked 100 yards into the trail. Turn right for the Fire Road. The climbing begins in earnest at this point, and heads up to the East Ridge on Cowles. The ridge plateaus for a 1/4 mile or so and then steepens again to the upper "S" sections. ( I'd call them switchbacks, but on a 12 foot wide fire road, its more of an "S") Climb these "S" sections to the top. Total hike: 3 miles round trip. Don't be fooled by the fact that there is only 900 feet of elevation gain: 400 feet gains in the last 1/4 mile.
Hiking shoes or boots. Many people that are training to do Mt Whitney use this climb to prepare and will fully pack up and bring their boots instead of running shoes.
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