This trail is near the eastern border of Golden Gate Canyon State Park. To reach it, get to the intersection of highways 93, 58 and 6th avenue (This is the mouth of Clear Creek Canyon). Go north on highway 93 (Towards Boulder) about a mile to a signaled intersection of highway 93 and Golden Gate Canyon road. Turn left (west) and go up the canyon. For those of you familiar with the White Ranch, you will be heading in the direction of the upper parking lot. As you go up the canyon, take a right at a road just past the Grange building called Crawford Gulch. I am guessing it's about 5 miles up the canyon. Be on the lookout for signs pointing you to White Ranch. Follow them. While you will not end up at White Ranch, you will fly right past it. Take Crawford Gulch all the way past the last turn to White Ranch, which will take you on a dirt road. Enter Golden Gate State Park from the east and pull off at the Nott Creek trailhead. Make sure you grab a parks pass envelope at the entrance and pay the $5 fee. Park at Nott Creek and hop on Mountain Lion Trail. Follow it clockwise--and this is crucial. (The opposite direction is just not rideable for long stretches). The trail climbs hard for about 1.5 miles, levels out for a half mile, then climbs for another mile or so. Then it's a technical descent (Rocky and rooty) along a creekbed until a rolling uphill exit. ALTERNATE ROUTE TO THE TRAILHEAD: Take Golden Gate Canyon road ~ 20 miles to the ranger station (Look for signs) and stop in for directions to the Nott Creek parking area (4.7 miles away).
Summary: I too found this trail in a Falcon Guide. Boy was I in for a surprise. This is the most challenging Front Range ride I've done, primarily for the technicality. As some other reviewers mentioned, many sections of the ascent are so steep that once you stop (due to an obstacle that you can't clear or to take a breather), it's very difficult to get started again (think very steep terrain, add in a few inches of loose dirt/sand, and many large rocks/drops). Most of the trail is rideable, but several sections will challenge even the most experienced riders (in terms of aerobic ability and technical skills).
The descent, particularly following the creek, is FUN, but again, very technical. I'm sure my 29er wheels helped me stay upright and avoid the many wheel-grabbing rocks. :-)
I've ridden Bergen Peak several times; compared to the Mountain Lion route, Bergen is a piece of cake.
FYI, one of the other reviews mentioned going all the way to Windy Peak. As of Aug. 15 2011, the trail from Mountain Lion to the peak is for hikers only, which could explain why that section is seemingly impossible to ride.
Summary: i read about this ride in the Falcon Guidebook and was excited to try this physically 'moderate' and technically 'moderate' trail with only "800 ft" of climbing (according to the supplied elevation profile). if i only would've known. there's not a lot of reviews out there about this trail so i'm going to add my two cents.
this trail is physically challenging, technically brutal, and its about 1000 ft to the saddle but atleast 1300ft to the top of windy peak. speaking of windy peak, the author says it just a quick jaunt to the peak and on the elvation profile it shows the peak lower than the top of the saddle. the climb to the saddle starts off doable then gets very steep. however, the climb to windy peak will eat you for lunch. no one, no matter how strong a rider you are is going to 'clean' this. loose scree, big rocks, steep, and tight thru trees. the downhill from windy peak is even more sketchy. i got up there and saw 5 hikers amazed that i brought my bike up there. they asked "you rode that up here?" i replied, "nope. pretty much carried it up here." they laughed, i cried.
the descent to the creek is technical as it gets. roots and loose rocks rule here. baby heads are here too and they will buck you over the bars if you're not paying attention. there's a few spots that can and will grab your tire and you will be sent flying. there's plenty of stream crossings too. some are rideable but most aren't.
i would not recommend riding this solo or on a hardtail or if you are relatively new to mountain biking. there is nothing "moderate" about this trail. don't let me deter you from riding this trail. it's great if you love a technical challenge and the view atop windy peak is as good as it gets. just a fair warning: if you let it, Mountain Lion will eat you alive. be careful.
Recommended Route: clockwise. CCW is pretty much unrideable. climb to windy peak for the view but you will be hiking your bike a lot.
Summary: This is a classic, but only for experienced riders. Novices will get hurt, or they will spend an inordinate amount of time walking their bikes. I wouldn't do this trail on a hardtail--but then again, hardtail aficionados are a hardy bunch. The beginning climb is over loose sand resting on top of hard-packed quartz. The surface is off-camber and rutted. Not to the extreme, but enough to challenge hard-core climbers. Skilled riders will not dab, but most of you will, once or twice. Kudos to you if you can clean the initial 4 miles. The only way that will happen is if you're fit and technically proficient... Period.... Then you'll flatten out a bit and ride on a jeep road for a mile or so, until you get to the next uphill grunt. It's a switchback climb over golfball-sized loose rock. I don't have to tell you this adds a bit of a challenge to the steeper sections, where traction is found at a premium. Once you crest this do-able climb, you weave downward though a lodgepole forest, taking some drops through ruts and roots. Fun stuff!! Then you reach the creekbed and bounce along the cobble, over tree bridges or through shallow crossings. Look out for the wheel-grabbing gnomes; they're all over the place. I endo'd three times the first time I rode this, but I've made a mental note or two of the places and spaces that require a bit more speed. Now I just rack myself once in a while. All I can say is pick a good line and hang on. After all the bouncing, you'll emerge onto a double-track which will rise and level three times. If you're riding with someone (You really should have someone along for safety) this is a great place to start the sprint back to the trailhead. It is still a couple miles away, but certainly a great place to duel it out (If that's your thing; Personally, I like to crank it up!). Finally you'll drop down to the parking area and finish up the ride. Relish this puppy--it's a gem!
Recommended Route: Clockwise from the Nott Creek parking area.
Other recommended trails in the same area: White Ranch: Epic Loop (Belcher-Longhorn-Wrangler)
Chimmney Gulch-Windy Saddle-Apex