Large Vehicles

This page is about changes coming on June 7, 2026.

For current Zion-Mt. Carmel Highway and tunnel information, visit our tunnel passes page.

 

The affected highway area includes many tight curves, narrow passes, and old bridges.

NPS Photo / Wil Marischen

Beginning June 7, 2026, Zion National Park will enforce existing size and weight limits on the Zion-Mt. Carmel Highway (ZMCH) from Canyon Junction to the East Entrance. This page explains who is affected, where the restriction applies, and why the restrictions are being implemented.

What's changing?

Starting June 7, 2026, vehicles that exceed any of the size or weight limits outlined below will not be permitted to drive the Zion-Mt. Carmel Highway between Canyon Junction and the East Entrance.

Please note: These restrictions apply to the entire section of highway between Canyon Junction and the East Entrance, not just the Zion-Mt. Carmel Tunnel.

 

Length, width, height, and weight are all considered under the restrictions.

NPS Photo

What is a "large vehicle?"

Your vehicle is considered a "large vehicle" if it exceeds any of these limits:

Single Vehicle Size Limits

For single vehicles without trailers / "pull-behinds," the limits are as follows:

• Length: 35'-9" (10.9 m)

• Width: 7'-10" (2.39 m)

• Height: 11'-4" (3.45 m)

• Weight: 50,000 lbs (22,680 kg)

Combined Vehicle Size Limits

A combined vehicle is any motor vehicle configuration made up of two or more seperate units that are physically connected at a pivot point and operate together (for example, a truck with a trailer).

For combined vehicles, the limits are as follows:

• Total Length: 50'-0" (15.24 m)

• • Trailer length cannot exceed 26' (7.92 m) from hitch to rear axle.

• Width: 7'-10" (2.39 m)

• Height: 11'-4" (3.45 m)

• Weight: 50,000 lbs (22,680 kg)

Please note: Measurements include mirrors, tires, and attachments such as AC units, bike racks, satellite dishes, or other after-market modifications.

 

What to expect at entrance stations

If your vehicle exceeds the limits and you arrive at the park's South or East Entrances, you will be given instructions for turning around safely. The only exceptions will be those entering the park through the South Entrance who are:

• Parking in the large vehicle lot by the Zion Canyon Visitor Center and there is room

• Visiting Zion Lodge (pass required)

• Driving the Zion Canyon Scenic Drive during the shuttle off-season

• Camping in Watchman Campground or South Campground (once open)

 

Cars of the early 1900s were much smaller than today's vehicles.

Zion Museum Catalog No. 10174

Why the restrictions are needed

Safety on a historic road

These limits are based on two safety studies conducted in 1989 and 2019 and validated by the U.S. Department of Transportation's Federal Highway Administration.

The studies found:

• Single and combined vehicles longer than the established limits can't safely maintain their lane on the highway's tight curves and switchbacks.
• Vehicles wider and/or taller than the limits can't pass through the Zion-Mt. Carmel Tunnel in a single lane of travel.
• Vehicles heavier than 50,000 lbs exceed weight limits on four bridges along the highway.

Protecting America's cultural history

Completed in 1930, the Zion-Mt. Carmel Highway is listed on the National Register of Historic Places and is a Historic Civil Engineering Landmark. Its tunnels, bridges, and switchbacks were engineered for smaller, lighter vehicles, and large vehicles increase the risk of damage to historic infrastructure that was not designed to accommodate them.

The ZMCH was intentionally designed as a scenic experience that harmonizes with the landscape. Limiting vehicle size helps preserve this nationally significant roadway for current and future generations.

Improving visitor experience

Under the current tunnel pass/escort system for large vehicles, one-way traffic creates significant delays: a 2016 study found there was an average of 19 minutes of free-flowing traffic through the tunnel out of each hour, with the busiest day having only eight minutes.

 

Frequently Asked Questions

What are the alternative routes?

There are numerous state highways that bypass the Zion-Mt. Carmel Highway. Common routes to common desinations are as follows:

• To get to Bryce Canyon, travellers can take Highway 20 (north of Cedar City). This route adds about 63 miles or 42 minutes.

• To get to the Grand Canyon's North Rim, travellers can take Highway 59 southeast towards Jacob Lake. This route only adds about 23 miles or 10 minutes to the trip.

Other routes can be found on your navigation platform / app of choice.

Why not enlarge the highway to accommodate large vehicles?

The majority of the ZMCH is adjacent to land federally protected under the Wilderness Act of 1964. Expanding or widening the road is not possible without harming the park’s wildlife, plant life, geological features, wilderness character, and historic resources.

Can RVs still visit Zion?

Yes. RVs that meet the limits may transit the ZMCH. If an RV exceeds limits, visitors can still access Zion through the South Entrance, where parking and camping options are available (as conditions allow). However, RVs exceeding limits will not be permitted past Canyon Junction.  

Do I have to pay the park entrance fee if I am "just passing through" Zion National Park?

Yes. The US Congress has designated Zion National Park as a US Fee Area. You are required to pay the entrance fee to enter the park. Fee exemptions are made for locals in surrounding communities who must meet certain criteria.