Located just west of downtown San Luis Obispo, the 1,292-foot Cerro San Luis (or San Luis Mountain) offers sweeping views over the city and surroundings. Cerro San Luis is a member of the Morros, or Nine Sisters, a chain of prominent volcanic peaks stretching east from Morro Bay. These beautiful peaks set the postcard-like backdrop for San Luis Obispo and are excellent places to hike.
Several trails explore Cerro San Luis, and its proximity to downtown makes it quite popular with hikers. The main trail to the summit begins from the end of Marsh Street just before the on ramp to Highway 101, providing a four mile out and back hike with 1,100 feet of elevation change.
Variations: The hike up Cerro San Luis can be converted to a 5-mile round trip hike by using an alternate trail in one direction to loop back through other areas of the mountain. Lemon Grove Loop Trail overlaps the first half-mile of the hike and can be tacked on to the trek to extend the hike by 1.5 miles. Another alternative is to hike 5.7 miles round trip from Laguna Lake Park to the summit of Cerro San Luis.
Just a tenth of a mile from the trailhead, stay to the left through a junction with Lemon Grove Loop Trail. Angle northwest up the skirt of the peak through a mixture of Prickly peak cactus and sage. After passing a restful park bench, make another left, half a mile from the start, to leave Lemon Grove Loop Trail on a track to the summit. Turn left again when you meet a path heading back toward Lemon Grove Loop Trail.
Cross the southern side of the mountain. Go through an oak grove and stay to the left through a junction with “M” Trail, which climbs up to the white “M” on the side of the mountain. The “M” represents Mission Prep School, the way the P on Yucca Ridge represents Cal Poly. Beyond the letter, “M” Trail descends toward Lemon Grove Loop Trail, opening up other loop options, like Lemon Grove and “M” Trails Loop.
Stay on Cerro San Luis Trail past the “M” Trail. Continue west until you reach a wide dirt road, one mile from the start. This road was bulldozed by an angry Alex Madonna after the city denied his petition to build an alpine-themed convention center at the top of Cerro San Luis. To the left, the road descends to the stables behind Madonna Inn. Part of this trail is also used by hikers making the extended ascent from Laguna Lake Park.
Turn right and hike the final mile up this broad trail to the summit. After 0.4 miles, the trail bends around the northwestern slope of the mountain to offer a fantastic view of Bishop Peak. Three other Morros, Chumash Peak, Cerro Romualdo, and Hollister Peak, can also be seen from this vantage point.
The trail swings up the north side of the mountain as the vegetation thickens. Coast live oaks provide occasional shade, while Indian paintbrush, morning glories, Lupines, monkeyflower, and other wildflowers add splashes of color along the trail in the spring.
Cal Poly and the Santa Lucia Mountains fill the view as the trail switches up to a short loop circling the top of the peak. Turn right or left and make your way east to the summit. Amble up a pile of boulders and take in the 360-degree views from the top of Cerro San Luis.
A white platform at the top of the road is used to hold special church services. Around Easter, a tall white cross stands atop the summit, and at Christmas there are lights in the shape of a tree. Neither construction interferes with the sweeping views over San Luis Obispo.
From the summit, head back the way you came or descend via the alternate trail (backside trail) to extend the hike from four to five miles.
From the top of Cerro San Luis, make your way a tenth of a mile back along the southern side of the loop and locate a trail dropping off the mountain. Head down the trail for the 5-mile loop, making a left through a junction after a hundred feet. This wide track curls around Cerro San Luis in a counter-clockwise direction from south to east to north to west to eventually reconnect with the route you took up. This longer “backside” route is less crowded and offers different perspectives to enjoy.
A short distance from the top of the trail, there is a nice perch looking south. Proceed another 0.2 miles and come to a overlook by a large bounder where there are views east over San Luis Obispo. The trail enters an oak forest from here and becomes rocky as it descends the mountainside. Meet a junction on the northeast side of the mountain, 3/4 of a mile from the top. Make a left to continue around the mountain. Alternatively, turn right to drop down into a pasture north of Lemon Grove Loop Trail. On the connector trail, bear right through unmarked to junctions to reach the Lemon Grove for a shorter route back to the trailhead. The backside trail continues another 1.25 miles around the skirt of the mountain, offering a close-up of Bishop Peak before angling uphill to meet the broad dirt trail on Cerro San Luis, directly across from the trail coming up from Marsh Street. Go straight across the road to travel one mile back to the trailhead, retracing the route at the start of the hike.
The trek to the summit of Cerro San Luis begins in a city-owned open space. The Madonna Family owns the mountain itself, but grants public access to hikers and mountain bikers. Dogs are welcome. No fee or permit is required to hike up Cerro San Luis, 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: 35.2749, -120.67237 (35° 16′ 29.6″N 120° 40′ 20.5″W)
|"M" Trail |
This extensions off the trail up Cerro San Luis makes its own 1.9-mile round trip hike to the large white "M" installed halfway up the east side of the mountain.
|Lemon Grove Loop Trail |
This 2.2-mile loop visits a historical lemon grove on the eastern slopes of Cerro San Luis.
|Lemon Grove & "M" Trails Loop |
This 2.4-mile hike uses all of the "M" Trail and part of Lemon Grove Loop Trail for a scenic circuit on the east side of Cerro San Luis.
|Cerro San Luis from Laguna Lake Park |
This 5.7-mile hike summits one of the Nine Sisters just west of downtown San Luis Obispo.
|Bishop Peak |
This 3.5-mile hike ascends 950 feet to highest summit in the Nine Sisters, offering excellent views of San Luis Obispo and the surrounding Morros.
|Felsman Loop Trail |
This 2.7-mile loop crosses oak, sagebrush, and grass-covered slopes around the base of Bishop Peak, providing excellent views of that notable rocky summit and its San Luis Obispo surroundings.
|Terrace Hill |
This 0.55-mile hike tours a flattened mountaintop in the city of San Luis Obispo that hosts panoramic views of the surroundings.
|South Hills Ridge Trail |
This 1.5-mile round trip hike ascends 425 feet to the highest point in a cluster of hills near downtown San Luis Obispo, offering fine views over the city and surroundings.
|Islay Hill |
This 1.8-mile round trip hike climbs 550 feet to the top of San Luis Obispo's easternmost Morro.
|Reservoir Canyon |
This 5.35-mile hike ascends 1,350 feet past a waterfall and a collection of junk sculptures to a treeless summit overlooking San Luis Obispo.
|Poly Canyon Design Village |
This 2.5-mile hike visits an experimental architectural village designed by Cal Poly students at the base of the Santa Lucia Mountains.
|More hikes in San Luis Obispo |
Explore other trails around San Luis Obispo including Morro Bay State Park and Montaña de Oro State Park.