​Right next to Fullerton Fire Station No. 6 on Rosecrans is the entrance to a little-known outdoor route called the Castlewood Trail, which is listed on the City of Fullerton Parks & Recreation Department’s website as a 1.33-mile connector trail. Offering fantastic  views of Orange County, the Castlewood Trail is primarily used by bikers, horseback riders, and local hikers to travel between Rosecrans Avenue and the corner of Castlewood Drive and Gilbert. On an overcast morning in early June, I had a chance to explore this mile-long connector trail and take a look at a closed-off portion of Coyote Hills hidden behind a barbed wire fence.

According to a May 6, 2001 Los Angeles Times story by Jerry Hicks,  the surrounding Coyote Hills area “just north of Rosecrans Avenue between Euclid Avenue and Beach Boulevard,” which borders the Castlewood Trail,  was once an “oil field, dating back to 1890. But the wells have been capped for years. All that’s left is an old maintenance road and a radio tower.” Both of which I saw while out hiking.

Parking at the far end of an asphalt lot on the outskirts of a baseball field across from Ralph B. Clark Regional Park, I walked along the sidewalk on the north side of Rosecrans  until I reached Fullerton Fire Station  No. 6 and the adjacent Castlewood Trail entrance. If you do plan on parking by the baseball field, please note the hours. Along the stretch of natural open space between the flat parking lot and fire station, I spotted cacti, a lot of dry vegetation, and a closed-off fire road that led into the rugged terrain of a blocked-off portion of the nature preserve.

The entrance to the Castlewood Trail is marked by a sign with an arrow pointing to two wooden posts. This pathway, lined by trees, turns left, while the Rosecrans Trail continues straight, following the road. One of the Castlewood Trail’s only trash cans can be found here at the beginning, so make use of it. Before starting on this trail, remember to bring a large water bottle with you while hiking because it’s important to stay hydrated while out on Fullerton hiking trails. Open space is on the left side of the trail behind a chain-link fence  and  neighborhoods are on the right.

Coastal Sage Scrub is the plant community that largely makes up this biodiverse natural space. This means that you’ll encounter a lot of California sagebrush and buckwheat, among other types of vegetation on this trail. According to the Friends of Coyote Hills webpage titled “A Critical Habitat and Biodiversity Hotspot,” the natural rolling terrain on the other side of the fence “is home to 15 sensitive, rare, and endangered species and is home to some of the last remaining Coastal Sage Scrub plant community found only in California and northern Baja. More than 90% of the world’s Coastal Sage Scrub has been lost to urbanization.”

Following the fence uphill on the Castlewood Trail, I spotted buckwheat and prickly pear thriving in various areas of the blocked-off nature preserve. This plant life was also  noticeable along the sides of the pathway. There was an abundance of faded yellow “Trespassing/Loitering – Forbidden by Law” signs posted, warning pedestrians that they would be fined by Chevron if found on the privately owned Coyote Hills land.

Cul-de-sacs from surrounding suburbs occasionally connect to the Castlewood Trail. For the most part, the path bridges the gap between subdivisions and the open natural space of Coyote Hills. According to the Discover La Mirada website, the Castlewood Trail is a part of the 12-mile Fullerton Loop, a network of pathways popular among cyclists. At many points along this trail, cyclists have made their own off-road routes. One steep uphill bike path is worth taking just for the scenic panoramic views of Orange County. It branches off the flat Parks & Recreation Dept. trail right after turning a corner by the cul-de-sac at the end of Coyote Hills Drive. I recommend following the middle of the three narrow uphill bike trails (past some prickly pear cacti) to reach the top of a hillside covered by trees. All three bike trails leading up here do involve steep climbs uphill. Here, on a clear day, you could look between the trees to see all the way out to the ocean.

Staying on the bike trail as a hiker, it’s important to listen for coming  cyclists because at certain points along the hilltop trail, there isn’t much space to move aside. A tunnel of trees and lush vegetation on top of the hill make this way much more venturesome  and scenic than the flat paved pathway made by the city. This branch of the trail also allows hikers to see over the Chevron fence, providing picturesque views through the preserve’s  canyons.  Birds are also very active in the trees at these higher elevations. This bike trail continues onward for quite a ways before eventually winding downhill, turning into a concrete drainage channel before connecting back to the flat main section of the Castlewood Trail.

At this point, the path curves around a large pale green water tank surrounded by a chain link fence. Moving uphill following a white fence, the Castlewood Trail eventually splits next to a small brick utility structure: one way leads down toward N. Gilbert Street, while the other pathway leads toward a small park off Somerset Lane, with Palo Verde and pepper trees providing much-needed shade. Some of the wooden benches at this rest area are really worn down.

The Castlewood Trail continues onward and maneuvers over more hills, staying above the neighboring nearby homes before sharply angling downhill to reach the intersection of Gilbert and Castlewood Drive.  Overall, this is one of the most  scenic and strenuous connector trails in Fullerton, providing rare  picturesque  views of the privately  owned portion of Coyote Hills.