The Zion-Mount Carmel Tunnel

Construction of the 1.1 mile Zion-Mount Carmel Tunnel began in the late 1920s and was completed in 1930. At the time that the tunnel was dedicated, on July 4, 1930, it was the longest tunnel of its type in the United States. The Zion-Mount Carmel Tunnel (and the Zion-Mount Carmel Highway) provides direct access for travel between Bryce Canyon, Grand Canyon, and Zion National Parks. Learn more about the tunnel project's history and construction.

Important Update

Beginning in mid-2026, large vehicles will be rerouted from the Zion-Mount Carmel Highway to improve safety and protect resources. The maximum vehicle size that will be allowed to drive the Zion-Mount Carmel Highway will be no more than 7’ 10” (2.39m) wide, 35’ 9” (10.9m) long and 11’ 4” (3.45m) tall and 50,000 pounds. Oversized vehicles can drive around the park on existing roads, which will add an estimated ten to forty minutes trip, depending on route and destination. Learn more on this webpage.

Tunnel Traffic Control for Oversize Vehicles

Background

Before 1989, large vehicles, including tour buses, motor homes, and trailers, were involved in more and more accidents and near-misses in the tunnel due to a significant increase in the volume of traffic and in the size of vehicles passing through the tunnel.

A study by the Federal Highways Administration in early 1989 found that large vehicles could not negotiate the curves of the tunnel without crossing the center line. To ensure safety, the National Park Service began traffic control at the tunnel in the spring of that year.

Rangers posted at both ends of the tunnel convert two-way tunnel traffic to one-way for larger vehicles. This allows for safer passage.

Hours of Traffic Control

The tunnel is open to large vehicles from 8:00 a.m. to 4:30 p.m. every day. If you require an escort, please plan to arrive to a vehicle entrance no later than 4:15 p.m. Drive time to the tunnel is at least 15 minutes from either vehicle entrance. Permits will not be issued later than 4:15 p.m. each day to ensure those issued a permit are provided an escort.

Do not drive a large, oversize vehicle through the tunnel when rangers are not present to manage traffic. Standard sized passenger vehicles can go through the tunnel whether rangers are present or not, 24 hours a day 7 days a week.

 

If your vehicle is 11'4" (3.4m) tall or taller or 7'10" (2.4m) wide or wider, including mirrors, awnings, and jacks, you will need a tunnel escort.

Obtaining a Tunnel Permit

• Have your vehicle measured at the entrance station when you arrive at the park. Any vehicle that is 7 feet 10 inches (2.4 meters) in width and/or 11 feet 4 inches (3.4 meters) in height or larger is required to have a tunnel permit.
• Pay $15, in addition to the park entrance fee, for the tunnel permit at the entrance station before proceeding to the tunnel.
• Drive to the tunnel between 8 a.m. and 4:30 p.m.
• Tunnel traffic control will be provided NPS rangers.
• Your $15 tunnel permit is good for two trips through the tunnel for the same vehicle within seven days of purchase.

Prohibited in the Tunnel

• Vehicles over 13 feet 1 inch tall
• Semi-trucks
• Vehicles carrying hazardous materials
• Vehicles weighing more than 50,000 pounds
• Single vehicles over 40 feet long
• Vehicles and trailers with combined length over 50 feet
• Bicyclists
• Pedestrians

 

The Zion-Mount Carmel Tunnel today

Today, the tunnel is very similar to how it was upon its completion over eighty years ago. Because the tunnel passes through soft sandstone, it has been reinforced throughout the years. Concrete ribs have been installed to give added support to the tunnel’s entire length.

In 1958, collapse of a sandstone pillar west of Gallery #3 broke the top out of that gallery and flushed tons of debris into the tunnel, causing it to close for several weeks. Because of that collapse, the tunnel is now monitored electronically twenty-four hours a day to warn park officials of potential rockfall danger.

 

Your Safety

The Zion-Mount Carmel Tunnel is one of the busiest areas in the park. Through the years there have been major and minor accidents as well as many close calls involving pedestrians, oversize vehicles, tunnel ranger staff, and regular vehicle traffic.

• When approaching the tunnel be aware of your surroundings and slow down. Watch for tunnel rangers, pedestrians and other traffic.
• Do not stop in the tunnel.
• Do not try to turn around at either tunnel entrance. Proceed beyond the tunnel kiosk before attempting to turn around at either side of the tunnel. Obey all traffic directions from the tunnel rangers.
• Be aware that rangers at the tunnel are conducting traffic control operations.

 

Frequently asked questions about the Zion-Mount Carmel Tunnel

When was the road built?

The Zion-Mount Carmel Highway, including the tunnel, was constructed from 1927 to 1930 at a cost of $1,896,000.

Do I have to pay the entrance fee if I'm "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.

Why do I have to pay a tunnel one-way traffic control fee?

Zion National Park charges $15 for oversized vehicles for the one-way traffic control service through the Zion-Mount Carmel Highway Tunnel. The purpose of the fee is to offset the cost of ensuring safe passage for oversized vehicles. The Zion Tunnel has been the site of numerous vehicle accidents through the years. With the tunnel one-way traffic control system in place, safety for all vehicles has improved greatly.

How many times can I go through the tunnel in my oversized vehicle for the $15 fee?

The fee is good for two trips through the tunnel with the same vehicle in a seven day period.

Do I get a discount on the tunnel fee if I have a Senior Pass or Access Pass?

No. The fee is the same for everyone who is driving an oversized vehicle.

What are the size limits for an oversized vehicle?

Any vehicle that is 11 feet 4 inches high or higher and 7 feet 10 inches wide or wider needs the one-way traffic control service. Any vehicle 13 feet 1 inch high or higher cannot pass through the tunnel.

Length restrictions are 40 feet for a single vehicle and 50 feet for any vehicle combination.

This information is also listed on the back page of the Park Newspaper. Visitors must pay for the one-way traffic control service at any Zion entrance station - not at the tunnel.

Will I be following an "escort vehicle" through the tunnel?

You will not follow an escort vehicle. Park rangers are stationed at both ends of the tunnel and will convert traffic flow to a one way direction. When it is safe for you to drive your oversize vehicles down the middle of the tunnel, rangers will allow you to proceed.

How long is the tunnel?

1.1-miles. It was completed in 1930 by the Nevada Construction Co. The project, including building the Zion-Mount Carmel Highway, took 3-years to complete and cost $1,896,000.

What is the elevation gain up to the tunnel and how far is it from the Visitor Center?

The elevation gain is 800 ft. and approximately five miles from the Zion Canyon Visitor Center.