ZION NATIONAL PARK — Zion-Mt. Carmel Highway and Tunnel will be dedicated Friday as a National Historic Civil Engineering Landmark.

The public is invited to the dedication ceremony at the South Campground Amphitheater in Zion National Park at 2 p.m. to celebrate the designated.

American Society of Civil Engineers President Andrew W. Herrmann and Zion National Park Superintendent Jock Whitworth will host the dedication ceremony.

The Zion-Mt. Carmel Highway, a leg of state Route 9, travels up Pine Creek Canyon, through the Navajo sandstone cliffs and east across the slickrock of the plateau. Over a three-year period, this improbable route presented unique and dangerous challenges to the construction crews. The crews began work on opposite ends of the road. On the western side, a series of six switchbacks were carved from the canyon floor up. On the eastern side, crews blasted their way through a sea of slickrock sandstone.

The most significant challenge was the arduous task of constructing the 1.1-mile tunnel through the heart of Zion's sandstone cliffs. On July 3, 1930, work was completed, and the Zion-Mt. Carmel Highway and Tunnel were officially opened to the public.