From Mission Gorge Road take Mesa Road and look for a park on your right hand side. You start from Big Rock Park on Mesa Road in Santee. I usually just park on the side of the road right next to the park on Mesa Road. The trailhead signs are right next to the park on the right hand side of the road.
You skirt around the park and follow the trail past some houses. You pass over a seasonal creek, which in the winter and early spring can carry quite a bit of water off the mountain.
You gradually start to climb up a series of switchbacks through dense chapparal. The trail is well maintained, so it's no problem getting through this. After about a 1.5 miles you intersect with a fire road(Barker Way Route) and you make a right.
The trail flattens out for another half mile or so and then begins a fairly steep ascent to the top of Cowles.
If you want to add a little more mileage to the hike, you can follow the signs to Pyles Peak, which is about 2.5 miles round trip from the top of Cowles.
The Santee side of Cowles can be very hot and dusty in the summer, so bring extra water.
Bring extra water during the summer, this hike can get very hot in the summer.
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