State of California • Department of Transportation TRAFFIC ADVISORY __________________________________________________________

Date: November 29 , 2023

District: 4

FOR IMMEDIATE RELEASE

State Route 1 – Tom Lantos Tunnel (Devil’s Slide) Overnight Closure.

Northbound Tunnel, Monday, December 4th, 2023, 8:00pm – 4:00am.

SAN MATEO COUNTY — Caltrans has scheduled overnight closure of northbound State Route (SR-1) at the Tom Lantos Tunnel (Devil’s Slide). The closures are to facilitate drain cleaning.

Traffic Control Measures

One-way traffic control will be inplace to safely guide vehicles through the open southbound tunnel. Provisions have been made for emergency vehicle access.

One way traffic control will be through the open southbound tunnel. A pilot vehicle will guide motorist thru the southbound tunnel in one direction and then turnback to guide traffic in the opposite direction thru the same southbound tunnel.  This is the same procedure as a few weeks ago.

Closure Schedule

• Northbound Tunnel only – Monday, December 4 – 8:00 PM to 4:00 AM

Changeable message and directional signs will be in place to assist motorists traveling in the area.

The California Highway Patrol (CHP) will be on site during the closure.

Please drive with caution.

Slow for the Cone Zone and Be Work Zone Alert.

Caltrans thanks motorists for their patience while we work to maintain our state’s highways, bridges, and tunnels.

For real-time traffic, click on Caltrans QuickMap