Now the most important part - the trails I've run in my FJC so far! Green is for trails I ran mostly stock (no lift/skid plates). Please let me know if you can think of any ways for me to make this more useful.
Colorado
Barbour Fork - Snow run in mid-November 2011.
Bill Moore Lake - Did this one with Red Elephant and Mill Creek. Bill Moore was the downhill/exit and I don't remember it being much worse than a really rough dirt road in most places.
Black Bear Pass - Extremely scenic but fairly easy pass between Ouray and Telluride. My tires hate the switchbacks (rubbing)!
Bunce School Road - Easy trail that would be fine for a stock FJC. This road provides access to T-33A Plane Crash and Ironclads.
California Gulch - Did this as the exit route off of Poughkeepsie Gulch at FJ Summit in 2011 followed by Corkscrew.
Cascade Creek - A short but moderately challenging trail near Idaho Springs. Ran this after Devil's Canyon, which was also fairly short.
Cedar Mountain Road - Easy road connecting Metberry, Longwater, and Hackett gulches. Didn't drive the whole road - only as far as Hackett Gulch on the south end. From what I've heard, it's an easy dirt road the rest of the way.
China Wall - One of the first trails I did. I remember looking at the "wall" obstacle thinking it looked impossible then going back in the snow a number of months later and thinking it looked totally doable. Returning to this trail really showed me just how much my perspective has changed on my FJC's capabilities.
Chinaman Gulch - I ran this one almost completely stock (only had the OSA suspension armor and digger links at the time). I think the only way I made it through this one without demolishing my FJC was the expert spotting by Chuck and Matt (the Funtreks guys). This one still sticks out in my mind as the toughest trail I've done and I wouldn't recommend it for a stock cruiser. I *really* want to go back and see if it still seems as difficult. Update: I've been back a couple of times and it seems to get more difficult each time.
Chinns Lake - Easy but fun run up to some gorgeous lakes in the St. Mary's Glacier area.
Cinnamon Gulch - Short but fun spur off of Peru Creek, if my memory is correct.
Coney Flats - Very fun trail with mid-range difficulty. It was pouring rain when I ran it, so not sure how much water is normally on the trail. There was a ton this day!
Corkscrew Gulch - Exit off of Poughkeepsie/California Pass.
Cottonwood Pass - Did this one on the way back from FJ Summit in 2011. Half of it is paved, the other half is a dirt road suitable for a Prius.
Cumberland Gulch - Did this one with Yankee Hill and Miners Gulch. There's a maze of trails in this area!
Deer Creek - Easy exit from the top of Radical Hill down into Montezuma. Took me 15-20 minutes.
Devil's Canyon - A short and mild trail with one short, fun hill at the top. Was originally supposed to run this last winter as a snow run (with Barbour Fork) but we got stuck on Barbour Fork for too long and didn't make it. This would definitely be more fun with snow on it.
Eagle Rock - Snow run in mid November 2011. Pretty challenging as a snow run.
Fern Creek - I've run this a few times as an exit from Illinois/Missouri Gulches in the Rainbow Falls area. Easy but fun connecting trail to Rampart Range Rd.
Fireman Hill - One of the trails in the Left Hand Canyon area. I've run this one up/down/in the dark. Nice challenge for a stock FJC.
Geneva Creek - Easy but fun trail with lots of old mining roads to explore near the top.
Georgia Pass - Easy run up near Breckenridge.
Goose Creek Rd. - A dirt road through the Hayman Burn area with gorgeous scenery. Much more fun in the snow and a nice way to get to China Wall from Denver. Very first dirt my FJC saw!
Governor Basin - Fun trail in the Ouray area.
Grizzly Lake - Very difficult trail. There's a large ledge at the beginning that turned our group around the first time we tried it. Went back the next day and someone had done some extensive rock stacking so we were able to get over it without winching. The rest of the trail was a ton of fun with a very pretty lake at the end.
Hackett Gulch - One of the three gulches in the area (Metberry, Longwater, and Hackett). This one is furthest south and probably the second best, after Metberry. Saw a bear watching us near the beginning of the trail. This trail is easily passable by a stock FJ.
Hayden Pass - Did this one with my trailer in June 2011. Part of the weekend with Medano Pass.
Holy Cross - Very difficult trail! Picked up some more body damage when I slipped in some mud into a rock at the top of French Creek on the way back down.
Illinois Gulch - Fun play area named "Moab Hill" a little way into the trail. Otherwise, pretty mediocre.
Imogene Pass - Did this one at FJ Summit 2011. Fun, scenic, but very crowded trail.
Iron Chest - The first half mile or so of this one is through the worst boulder field I've been through. Large, loose boulders that change the line from truck to truck. On the way out, I had a boulder roll out from under one of my rear wheels and high center me on my frame. It was around a 3 hour recovery to get me unstuck...would've been much quicker if I had a winch at the time.
Ironclads - Slightly easier than T-33A Plane Crash trail, if you avoid the optional obstacles. This trail had some really fun optional stuff to play around on.
Last Dollar Road - Easy trail between Telluride and Ridgway (way more west of Ridgway than I'd realized). There's nothing technical on the trail, but it has a different feel compared with all of the other trails I've run in the area.
Kingston Peak - Easy and scenic trail in the Yankee Hill area. Don't forget to add a rock to the "rock cottage" up on top for good luck!
Left Hand Canyon - This is the closest trail complex to Denver/Boulder and I've lost count of how many times I've been up there. Lots of fun trails but also a lot of drunk college kids shooting guns so it's a mixed bag.
Loch Lomond - Short and moderate trail to a beautiful lake.
Longwater Gulch - One of the three gulches in the area (Metberry, Longwater, and Hackett). This one is honestly kind of boring and gives the same views as Metberry, without the payoff of the Platte River at the end. Easily passable by a stock FJ.
Medano Pass - Ran this one in mid June 2011 about a week after the high water point for the season on Medano Creek - the deepest crossings were still around 2 feet deep at the time. This was my first trail towing the trailer and it did excellent. Deep sand on the Great Sand Dunes side which was fun and pretty unique for Colorado.
Metberry Gulch - Scenic trail near the Hayman Burn area. Not very difficult, although there is one large obstacle (with a bypass) that could be impassable if it's wet.
Middle St. Vrain - Very fun and scenic trail. Enough of a challenge to keep things from being boring, but probably doable in a stock FJC.
Mill Creek - Did this as a connector between Red Elephant and Bill Moore Lake. There's a really cool public cabin along the trail and some fun water crossings.
Miller Rock - Picked up a ton of pinstripes on this overgrown trail. Fun run with an interesting exit - you have to call ahead to the private camp at the end of the trail to unlock the gate so you can go out the far side.
Mineral Creek - Easy but fun entrance to Poughkeepsie Gulch area.
Miner’s Gulch - Ran with Yankee Hill and Cumberland Gulch.
Missouri Gulch - Easy trail in the Rainbow Falls area.
Mosquito Pass - Highest pass in Colorado. Easy and crowded trail since it's only snow-free for a couple of months.
Ophir Pass - Easy return trip from Imogene Pass.
Peru Creek - Easy trail near Keystone.
Phantom Canyon - Scenic dirt road that's a fun way back from the Canon City/Royal Gorge area.
Poughkeepsie Gulch - The only challenging trail in the Ouray area that I've been on. Lost my passenger rear bumper wing on this one.
Radical Hill - Fun climb from the bottom of Webster Pass to the top of the mesa directly across from Red Cone. One rocky area in particular will cause problems (and may be impossible when wet) for stock FJCs. Awesome view at the top!
Rampart Range Rd. - Dirt road that connects to a bunch of other trails in the area.
Red Cone - Fun and moderate trail over 13K foot peak. The drive down off of the summit is fun for its steepness/pucker factor.
Red Elephant Hill - Very steep and narrow trail with one challenging obstacle. UPDATE: Recently ran this trail again and the main obstacle has become much more dug out and difficult. I would no longer recommend this trail for a stock FJC.
Shrine Pass - Easy dirt road used as a short cut to get back to I-70 after Holy Cross. Sometimes these things don't work out to be shorter, time-wise, but this one was.
Slaughterhouse Gulch - Easy trail with one steep, rutted out hill that is kind of fun.
Spring Creek - Challenging trail pretty close to Denver. EDIT 8/5/2012: The trail has gotten worse since I last ran it. Most of our group on this trip had to winch through obstacle #3. I would probably avoid this trail if you do not have a winch (or a friend with one in front of you).
T-33A Plane Crash - Surprisingly challenging, although not too bad. Would not recommend this for a stock FJC.
Tincup Pass - Easy and crowded trail.
Twin Cone - Moderate trail that has been made much easier in the past year due to grading/boulder removal. There are still a couple of play areas on the way up and the last hill above timberline hasn't been graded and may cause problems for a stock FJC.
Webster Pass - Took this from Montezuma out to 285. Pretty easy trail that you might not even need four wheel drive on. It was very wet when I ran it and I didn't have any traction issues.
Wheeler Lake - Challenging and very fun trail. The picture at the top of my thread is from and obstacle on this trail named "Flopper". Lost a valve stem near the top.
Yankee Boy Basin - Moderate and very scenic trail in Ouray area.
Yankee Hill - Moderate trail close to Blackhawk.
Utah
Fins ‘n Things - I was expecting more "fins" than "things". Fun trail but honestly kind of a letdown after Hell's Revenge. Still a nice challenge with the steepest slickrock sections I encountered on this trip.
Hell’s Revenge - My favorite trail! Not very technically challenging, but *very* high pucker factor and breathtaking scenery. Driving on slickrock is a ton of fun and this trail is almost all slickrock.
Poison Spider Mesa - Fun trail with some nice obstacles.
Tower Arch Trail - Mostly a dirt/sand road with some ledgy stuff in places.
Kokopelli's Trail - Unforgettable adventure with Volhoo, skersfan, Akosfj, FJeep, and Ace Brown (for about 1/2 the trip). First hardcore trip with the trailer. Had some route finding trouble in Cisco Wash, Dome Plateau, and along the beginning of Rose Garden Hill. Made the trip more memorable though!
Dome Plateau - Easy and scenic trail. Did this the opposite way than how it is described in the Wells' book as part of Kokopelli's. We weren't actually supposed to do the whole thing as part of Kokopelli's but didn't realize this until we got to camp and talked to Ace.
Top Of The World - Very ledgy trail and somewhat difficult. Trailer made the round trip. Extremely scenic and highly recommended!
Rose Garden Hill - We followed signs to Kokopelli's Trail at the very beginning and ended up doing a difficult and dangerous bypass. It was a fun bypass in my book. We went down the actual Rose Garden Hill obstacle...fairly difficult with a trailer. I high-centered on a tall ledge, jack knifed my trailer and almost got pushed over side ways by it and down the hill. Learned that I need trailer brakes before attempting anything like that in the future.
California
Rubicon Trail - By far the toughest and most relentless trail I've run! Extremely beautiful. We did this as a two-day run from Loon Lake to Buck Island - to Tahoe with Mile High Jeep Club Patrol 2. It rained the second day and made things way more difficult. Picked up some moderate (but cosmetic) body damage on Cadillac Hill on the way out. Wasn't a particularly difficult obstacle, but slipped off my line due to rain.
Buck Lake Trail - Moderate and little-used (guessing from the amount of overgrowth) trail off of the end of the Rubicon. Runs to gorgeous and secluded lake about 3/4 of the way up before connecting to Ellis Peak trail at the top. Some of the best views of Lake Tahoe and the Rubicon area of the whole trip.
Ellis Peak - Easy trail that's moderate in a few spots. Doesn't go all the way to the top of the peak, but gets you close. There are also a couple of lakes along the way, one of which had a canoe at it that we played around in. The hike up to the summit of Ellis Peak from the end of the trail is moderate/difficult. Very steep and requires some rock scrambling at the top.
Barker Pass - Ran this trail from Tahoe City back around to the end of the Rubicon Trail. Very easy dirt road type thing until it joins back up with the Rubicon, where it becomes more moderate in spots.