John Bull Trail: One of Southern California's Toughest 4x4 Runs

John Bull Trail has a reputation that precedes it. Mention the name around Southern California off-roaders, and you'll get knowing nods from people who've run it and wide eyes from people who haven't or not made it and limped home with a broken rig. I ran it for the first time three years ago with a group of experienced wheelers. Watched a guy in a heavily built Jeep on 37s struggle through the Gatekeeper for 20 minutes. The John Bull experience is hard, and time on the trail proves it.

Located in the San Bernardino National Forest near Big Bear, John Bull (Forest Service Road 3N10) is roughly 3 to 5 miles of relentless technical terrain. Boulder fields, steep climbs, off-camber sections, and obstacles with actual names. It's Big Bear's benchmark for what a properly built vehicle and an experienced driver can handle. If you're looking to test yourself and your rig at the limits, the John Bull Trail in Southern California is where you go.

John Bull Trail Background & Reputation

John Bull Trail earned its status as one of Southern California's hardest trails through decades of humbling confident drivers. The trail follows old mining roads through the San Bernardino Mountains, climbing to over 8,000 feet with views to Lucerne Valley in the Big Bear area. The history dates back to early mining operations in California.

What makes John Bull Trail different? Most difficult routes have major obstacles separated by easier sections. John Bull hits you immediately with the Gatekeeper and doesn't let up. The technical section runs about 2.2 miles of sustained difficulty. Vehicle-sized boulders, rock gardens, steep climbs. It's rated solid black diamond. This is not an easy trail.

The trail has achieved Jeep Badge of Honor status, drawing wheelers from across the country looking to test their builds and skills. Weekends can see traffic jams. Constant use and weather shift rocks and terrain continuously on this hard California trail.

Location, Access & Staging Areas

Navigating to John Bull can be confusing because the access roads are long and wrap around the mountains. There are two primary ways to enter the technical section of 3N10.

The Eastern Entrance (The Hard Way / Uphill)

This is the most popular entrance for those seeking the full challenge. It is located on the eastern edge of the trail system, closest to Baldwin Lake.

• • How to get there: From Highway 18 east of Big Bear Lake, follow signs toward the Big Bear Landfill (heading northwest). Turn left before the substation and follow Holcomb Valley Road (FS 3N16) uphill for approximately 2 miles. You will reach a junction where FS 3N10 branches off to the right.
  • The Experience: This is the "true" start. You are immediately confronted by the Gatekeeper obstacle. You will be climbing uphill through the rock gardens, which is the most difficult way to run the trail.

The Western Entrance (The "Easier" Way / Downhill)

This entrance is deeper in the mountains, closer to the Fawnskin and central Holcomb Valley area.

• • How to get there: You typically access this side by driving further west into Holcomb Valley via 3N16 or by coming up from Fawnskin via Polique Canyon (2N09). You will enter the 3N10 technical section from its western terminus (near the junction with 3N43).
  • The Experience: Running the trail from West to East allows you to descend most of the major obstacles, including the Gatekeeper at the very end. While still extremely technical, gravity is on your side, making it a better choice for first-timers.

Trail Connectivity

John Bull connects to multiple other trails at both ends. You can link it with Holcomb Valley trails, Gold Mountain, or continue west toward the Burns Canyon area.

Trail Overview at a Glance

Length: 3-5 miles, depending on start/end points (2.2 miles of sustained technical terrain)

Difficulty: Black Diamond / Expert

Time: 3-5 hours for well-equipped vehicles; can take significantly longer with traffic or if rigs struggle Elevation: Climbs to 8,100+ feet
Season: Typically May through November; snow closes it in winter
Direction: Can be run east-to-west (harder) or west-to-east (easier)

Requirements:

• 35-inch tires minimum (37+ better)
• Front and rear lockers
• Significant lift and high clearance
• Full armor (sliders, skids, bumpers)
• Winch
• Recovery gear
• Spotter(s)
• Group of at least 2-3 well-equipped vehicles

This is not a trail for stock vehicles or beginners. Period. Time on John Bull Trail demands proper vehicle preparation and group coordination.

Terrain & Obstacle Profile

John Bull's terrain is unrelenting granite boulder fields with steep climbs and off-camber sections. You're constantly reading challenging terrain, choosing lines, spotting obstacles. The rock is unforgiving with large boulders and rocky sections throughout. Make a mistake, and you're looking at body damage or getting stuck on this challenging terrain.

The surface transitions between large embedded boulders, loose rock gardens, and steep granite faces. Short wheelbase vehicles have an advantage where longer rigs risk high-centering. You need to navigate carefully through every section.

Expect deep ruts in sections where hundreds of rigs have carved the same lines. What looks like the right line might put your frame on boulders. A good spotter is essential on the steep climbs throughout the John Bull Trail.

Signature Obstacles to Expect

The Gatekeeper

The John Bull Trail's infamous opening act, thus its name. The Gate Keeper consists of vehicle-sized boulders requiring precise line selection. This sets the tone at the beginning of the technical section. Groups often spend 30+ minutes getting everyone through. You'll hit this obstacle right away on the Bull Trail.

There's no single "right" line. Different vehicles need different approaches. A good spotter here is critical for success.

Mid-Trail Rock Gardens

After the Gatekeeper, boulder fields continue on John Bull. Boulders follow one after another. Many more boulders appear as you progress. Multiple areas require choosing between tight gaps, steep angles, or direct climbs. What was easy last month might be hard this month.

Some sections have bypasses that are relatively easier but still difficult.

Upper Trail Climbs

As you gain elevation, climbs get steeper. Off-camber sections where you're leaned over at sketchy angles. Loose surfaces where tires hunt for grip. These demand precise throttle control.

Views from up top are spectacular. The views extend across to Lucerne Valley and beyond. But you're working too hard to enjoy the views until you've cleared the technical sections of the Bull Trail.

Recommended Ways to Run John Bull

Full Technical Run

The classic approach to the John Bull Trail. Commit to running the entire technical section. Plan on 3-5 hours minimum. Start early to avoid crowds. This is the complete experience on this Big Bear adventure.

Who it's for: Experienced drivers with fully built rigs who want to test themselves.

Partial Run & Turnaround

Not every group makes it through John Bull. Some realize at the Gatekeeper that continuing isn't smart. There's zero shame in turning around. Backing out is part of the experience.

If you turn around, communicate with other groups on the trail.

Who it's for: Groups testing their limits who remain realistic about capability.

John Bull + Holcomb Valley Combo

Link the John Bull Trail with the easier Holcomb Valley trails to create a full day. Plan to run John Bull in the morning when your group is fresh, then relax on Holcomb Valley. This adventure approach gives you variety.

Who it's for: Groups wanting the John Bull challenge but also enjoying the broader Big Bear experience.

Who it's for: Groups wanting the John Bull challenge but also enjoying the broader Big Bear experience.

Vehicle & Driver Requirements

Minimum Capable Setup

If you're asking whether your vehicle can do John Bull, it probably can't. The minimum is high, and this process is important:

• • 35-inch tires (37s better)
  • 4-6 inches of lift
  • Front and rear lockers for maximum traction
  • Rock sliders welded to the frame
  • Full skid plates
  • Winch (minimum 10,000 lbs)
  • Recovery gear
  • Armor everywhere the body meets rock

I've seen modified rigs on 40s struggle. I've watched Jeeps on 37s with the right driver make it look easy. This is a hard test of vehicle capability.

Ideal Trail Build

The rigs that handle John Bull comfortably have quality components:

• • 37-39 inch tires with beadlocks
  • Quality suspension
  • Dual lockers with 5.13 or lower gears
  • Full armor
  • Multiple recovery points
  • Onboard air
  • GPS with offline maps

This level of build gives you options and makes the experience less stressful.

Driver Skill & Group Considerations

Vehicle capability is half the equation. Driver skill and experience are the other half. You need terrain reading skills, throttle control, patience, and physical fitness.

Groups matter on John Bull. Running with a single vehicle is asking for problems. Three to four vehicles are ideal. Plan your group carefully. Every person should know recovery techniques to make the time on the trail productive.

Common Risks & Mistakes

Body damage is almost expected on John Bull. Sliders will get dented. Bumpers will scrape. Paint will be sacrificed.

Serious risks include high-centering on boulders, tipping on off-camber sections, breaking drive components, and damaging the oil pan or transfer case despite skids.

Common mistakes to avoid: attempting John Bull without proper preparation, running alone, starting late, ignoring spotters, using momentum where precision is needed, not airing down tires (18-20 PSI helps significantly). Be prepared for the challenges ahead.

Seasonal Conditions & Trail Status

John Bull typically runs from May through November. Winter snow closes it, usually from December through April. Spring openings depend on snowmelt. You'll want to find current conditions before making the trip.

Summer (July-August): Peak season. Expect weekend crowds. Afternoon thunderstorms make the rocks slick. Start early. Best time for dry conditions.

Fall (September-October): Cooler temps and fewer crowds. Best time to run John Bull.

Check conditions before going. Call San Bernardino National Forest at (909) 382-2790 for trail status.

Mapping, Navigation & Safety Planning

John Bull Trail shows up on OnX Offroad, Gaia GPS, and other off-road mapping apps. Download offline maps before you hit the trail. Cell service is unreliable. The app data will help you navigate even without a signal.

Safety planning essentials: Leave your itinerary with someone, carry first aid kit, bring extra food and water, have tools for repairs, check weather forecast, know your insurance probably doesn't cover off-road recovery.

The closest hospital is in Big Bear Lake. Forest Service rescues on John Bull happen multiple times per season. Plan accordingly.

Trail Etiquette on a High-Consequence Route

John Bull Trail sees heavy traffic. Etiquette keeps things moving:

Uphill traffic has the right of way. If you're descending, back up to a wide spot.

If a rig is hung up, wait patiently. Don't crowd them. This is considered good trail etiquette.

Keep your group together. Plan your options and communicate as a group.

Pack out everything. Broken parts, trash, everything.

Stay on the established trail. Don't create bypasses. Land managers watch this trail. Travel responsibly on John Bull.

Pro Tips for Tackling John Bull Trail

• Run it west to east (descending), your first time on the John Bull Trail.
• Air down to 18-20 PSI. The extra traction is a game-changer.
• Bring multiple spotters. A few things to watch for: hidden ledges, loose rocks, and tight gaps.
• Start early. Be at the trailhead by 7-8 AM. Time management is critical.
• Walk obstacles before driving them.
• Control your speed. This isn't a race. Groups that rush make expensive mistakes on John Bull.
• Bring tools and spare parts. U-joints break on John Bull. Being able to trail fix gets you home.
• If you plan to camp nearby, dispersed camping is available in the Big Bear area.

Final Thoughts

John Bull Trail isn't for everyone, and that's exactly what makes it special. It's Southern California's proving ground for serious 4x4 builds and experienced drivers. You'll learn more about your vehicle's limits in a few hours on John Bull than you will in a year of moderate trails. The Big Bear area offers this incredible challenge.

The challenge is real on the John Bull Trail. The risks are real. The satisfaction of completing it is equally real. This trail demands respect, preparation, and honest assessment of both your rig's capabilities and your driving skills. Don't let pride push you into situations your vehicle or skills can't handle. It's recommended to test your rig on easier trails first to save time and potential damage.

Before you attempt John Bull, make sure your rig is properly built. At Truck Brigade, we outfit Toyotas, Jeeps, Fords, and other 4x4 vehicles with exactly what you need for extreme trails. From suspension systems by King, Icon, and Fox to complete armor packages, and overlanding accessories and gear, we help you build rigs that can handle Southern California's toughest challenges.

Visit truckbrigade.com to get your rig ready for the John Bull experience. Feel free to contact us if you have a build in mind or a budget you have to work with.