Back to Frank G. Bonelli Regional Park for this edition of My Favorite Routes. Start with a stat: A good 75-80% of the time I head out for a spin on the mountain bike, I'll be at one of two places - Marshall Canyon / Claremont Hills Wilderness Park, or Bonelli Park. Truth be known, I can think of better places to ride the dirt, but due to their ease of access, and thus the frequency with which I ride there, they make the list. There are some similarities, for instance riding in both areas is dominated by dirt access, or fire roads, and trail use can be heavy. Mostly, though, each area is distinct from the other. There is only one stream crossing in Bonelli, the climbs are shorter and generally less steep, there is little single track, though I would say what s.t. there is is more technical.
view from Lower Beehive Trail
someone cough up a lung? - no, just a dried up cactus pad
On with the description. The hills of Bonelli Park are criss-crossed with trails. There are some nice ones near to the south shore of the lake, but since these are quite short, you would really have to combine these with others to get in a decent ride. The route that I tend to take is basically a perimeter loop of varied terrain. Every trail ride needs a starting point, and at Bonelli you have several options. You can enter the park from Via Verde and use any one of the ample parking lots along that road, you can forgo the entry fee and use the park and ride lot near the west Via Verde entrance, you can even park at Brackett Field near the restaurant. The last time I rode the loop I parked in the lot on the north shore (it must have been a weekday, since I didn't have to pay), and that is where this description starts (note the "S" in the white circle on the map). It is easy to pick up the trail here as it runs along the planted strip between the parking lot and Puddingstone Drive. It is fun and fast through here, basically singletrack; let it run. After passing the boat launch parking area you will make a sharp right onto a road that quickly turns to mostly gravel and circles along the edge of a retention basin, before dumping you down onto the paved road that crosses the dam.
Take this paved road over the dam, checking out the view across the lake to the left and the water slides of Raging Waters to the right. Watch for the occasional auto traveling the opposite direction on this one way access road. Once across the dam, merge onto Raging Waters Drive, keeping the lake on your left. Watch along the right of the road, in a short distance you will notice an old asphalt road branching off at a spot marked by some trees, and yellow gate posts with a chain strung between. Punch it up the short hill, but make a quick right at the dirt road switchback. This is the Lower Beehive Trail, which climbs and descends gently, and offers some nice views of the lake and San Gabriel Mountains. Before long you connect to the Upper Beehive Trail, which is steeper and takes you up to the high point on this side of the park. There always seems to be mountain bikers up here taking a rest; you can do so as well, or go straight into the descent off the top. You will bottom out with an option to go left and back to the paved Raging Waters Drive, or up a slight incline. Go up. This will take you to the tunnel going under Via Verde.
Exiting the tunnel take the wide sweeping turn left and run downhill behind the park headquarters. Being near the park entrance there tends to be many walkers and trail runners here so keep your head up and eyes open. You eventually come down nearly to Via Verde with a parking lot across the way. There is another yellow post and chain barrier, but you don't want to go there anyway. Instead keep to the dirt road which starts a gradual climb off to the right. At the next junction go right to keep climbing. You will shortly reach another junction, this one signed. This is an optional side route marked in yellow on the map and heads to the fire department reservoir at the top of the hill. It looks like a giant swimming pool with a view, but is enclosed by a fence, and is of course, off limits. There are some pine trees up here and on a hot summer day is a nice place to stop for a moment. When you have had your fill of rest head back the same way to the main route.
not the swimming pool
10 - 57 freeway interchange and Cal Poly Pomona
Shortly, and after a little downhill you reach a sharp turn marked by a transmission tower. I will often stop to take in the view of the I-10/SR-57 interchange and of the campus of California Polytechnic University, Pomona beyond. Continue down, along what is now the Coyote Trail, sections of which are steep and loose. Take this as slow or fast as your ability allows. You are riding along the 10 freeway now and its roar is an almost constant companion. Eventually you reach the low point along this road; off to the left is a wooden bridge, no longer used. The dry stream coming down from the hills here probably has some water when it rains, but I've never seen it. From here the road turns up again, the longest climb on the route; the grade varies, but nothing is especially taxing. Avoid any turnoffs until you practically reach Via Verde again. At that point, merge to the right and punch it up this short but rocky (bedrock, not loose) bit and notice the wide singletrack trail heading off to the right. Take it, though you could continue on the dirt road.
This is the longest bit of technical trail you will deal with on this route. There is a lot of cactus alongside you and some rocky sections to navigate and overcome. Steel your nerves and ride as much as you can. Keep your eyes peeled for a steep section leading up hill to the left, one which I must confess to never having ridden up - too steep and loose for me. Up top, at the end of the steep, is some sort of radar [?] facility. I used to ride a circle this taking in the views, but notice that they have now put up signs warning people not to linger due to radiation exposure, so now I hop back on the bike and quickly head down the paved access road. This takes you down to an intersection with Via Verde again, just outside the parks' east entrance booth. Cross the road looking for the obvious continuation of the dirt route, or take the equestrian undercrossing, and then pick up the trail again heading gradually up around the perimeter of the equestrian center. There is an interesting rock outcropping at the top of this section of trail with some colorful lichen covering the large rocks. Might be worth a stop if you are into that sort of thing. If not, just continue down.
This next portion of the route I have seen called the Crosby Trail, or the Rocky Trail, and it does indeed become quite rocky near the bottom. The rock is good solid bedrock, unforgiving, with some challenging ruts, but is doable, even by me. If you are not into that though, soon after topping out at the lichen rocks, take the detour to the left, the Corkscrew Trail, and marked by a sign. This detour is steeper with a loose surface, but is also less of a challenge. The two trails meet back together. Which ever you decide, check out the spot light on the tower to the right near the bottom. I have never been sure if this is some sort of relic, a part of the airfield, or used to find wayward golfers on the back nine of the adjacent golf course. I am guessing a combination of the first two, but the last would be much more fun. After things have leveled out, and at the junction go left. This will wind around below the public rv park, and come out at a paved access road running alongside the airfield and into said rv park.
some of what the Crosby Trail has to offer
At the locked gate hit the dirt service road on the right and fly down the little decline below some camp spots and into the Jungle. The road through here is clear and smooth, but deeply overgrown along its sides, in fact so deeply that the trees and shrubs form a tunnel enclosing you. You may catch glimpses of water and think you have entered a swamp, hence this sections popular name. Sometimes fluff falls from the cottonwoods; it is almost surreally different from anything else along the route. At the exit from the Jungle you reach the one stream crossing in the park. Sometimes this is easy, others it can be quite deep with wheel sucking mud at the entrance. Either way you have to cross, so do, go right on the access road alongside a picnic area, cross over the drive aisle / parking lot at any point and pick up the trail that runs alongside Puddingstone Drive. This is the same trail you started on, so take it back to the start, circle the park again, or hit up some of the other interior trails. There is a lot to offer. The loop as described finished off at slightly over 10 miles and slightly under 1400 feet of elevation gain.