“M” Trail on Cerro San Luis in San Luis Obispo

From downtown San Luis Obispo, it’s easy to spot the large white “M” on the side of nearest mountain, Cerro San Luis. If you’ve looked up at the “M,” you may have wondered what it’s like to look down from that big white letter, find out! The “M” is interesting to see up close and its perch provides a panoramic view over San Luis Obispo.

Hikers have a few ways to visit the the “M” representing Mission Prep High School:

“M” Trail is visible going up the right side of Cerro San Luis

The “M” is about halfway up the east side of Cerro San Luis. The easiest way to get there is to start from the trailhead at the end of Marsh Street on the west side of Highway 101 (that is actually on a short lane called Fernandez Road). This is the main trailhead for Cerro San Luis. Most of the hike to the “M” is in an open space owned by the City of San Luis Obispo, but the mountaintop is privately owned.

Leave the trailhead and hike a tenth of a mile to the first junction. Lemon Grove Loop Trail breaks off to the right and could be used as a hike extension. For the direct route to the “M,” bear left and continue up the main trail. If you’re interested in the Lemon Grove and “M” Trails Loop that covers all 0.95 miles of the “M” Trail, bear right and follow the directions for Lemon Grove and “M” Trails Loop.

After staying to the left at the first junction, go up the grassy slope another 0.4 miles to a junction with the top end of Lemon Grove Loop Trail. Switchbacks and other improvements have been added to the trail to make the ascent less steep. Stay left past the top of Lemon Grove Loop Trail onto Cerro San Luis Trail. Bear left at the next junction to stay on the main trail.

“M” Trail

After 0.65 miles of hiking, enter an oak grove come to a junction with the “M” Trail, which ascends to the right and reaches the “M” in just 0.3 miles. Leave the trail to the summit of Cerro San Luis and get on the single-track trail to the “M.”

“M” Trail climbs out of the oaks and across a sage-covered slope with nice views to the south and southeast over Edna Valley. Slip through a couple lines of oaks and more chaparral as the trail levels out and comes to the big white “M.”

The M on Cerro San Luis

The Cerro San Luis “M”

At the top of the trail, come face to face with the “M,” which is a concrete-formed letter embedded in the steep mountainside and painted white.

The “M” does not represent the Madonna Family, owners of property on Cerro San Luis (sometimes called Madonna Mountain). Instead, the “M” represents Mission College Preparatory High School, located in Downtown San Luis Obispo beneath the mountain.

Other schools have put up letters too, showing their school pride, which you can witness from this vantage. All the way to the north, above the university campus, you’ll see the Cal Poly “P” on Yucca Ridge. To the east, on the other side of downtown above San Luis High School on what is called High School Hill or Murray Hill, you’ll see an “SP” representing that institution. School pride aside, the views from the “M” are broad, covering downtown San Luis Obsipo and its surroundings.

Lemon Grove Loop Trail and downtown San Luis Obispo from the “M”

Hiking on from the “M”

Leave the “M” when you are ready and hike back. North of the “M,” the “M” Trail comes to an unmarked junction with a path that ascends Cerro San Luis. To the right, the “M” Trail descends for 0.65 toward Lemon Grove Loop Trail. The trail ahead takes a weaving cource down a rocky, oak-covered slope. Proceed with the “M” Trail if you’re hiking the Lemon Grove and “M” Trails Loop. To return to Cerro San Luis Trail, either to continue toward the summit or to return to the trailhead for the out-and-back hike to the “M,” simply turn around once you’ve seen the letter.

At the bottom of the “M” Trail, either turn right to hike another 1.35 miles up to the summit of Cerro San Luis or turn left to descend 0.65 miles back to the trailhead to complete the 1.9-mile out-and-back hike to the “M” with 560 feet of elevation change. No fee or permit is required to hike to the “M” on Cerro San Luis. Dogs and bikes are allowed, so get out and enjoy!

To get to the trailhead: From downtown San Luis Obispo, take Higuera Street southeast to Marsh Street and turn right. Pass beneath Highway 101, and turn right on Fernandez Lane (the only road on the right before Marsh Street turns on to the 101 South). Turn right into the dirt parking area. The trail begins at the end of the lot.

Trailhead address: 1183 Fernandez Road, San Luis Obispo, CA 93405
Trailhead coordinates: 35.274897, -120.672369 (35° 16′ 29.62″N 120° 40′ 20.52″W)


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