With the snip of a ribbon, officials on Monday unveiled the first tunnels built in California in more than 50 years.
The pair of single-lane tubes through the middle of a mountain will divert traffic from a treacherous 1.2-mile stretch of Pacific Coast Highway known as Devil's Slide that constantly erodes and frequently collapses about 15 miles south of San Francisco.
The old highway, built in 1937, will reopen in 2014 as a parkway for cyclists and hikers.
"Today, we mark the start of a new chapter for both Caltrans and the local communities," Caltrans Director Malcolm Dougherty said. "No longer will local residents and businesses have to worry about severe winter storms closing the road and disrupting their lives."
High school marching bands and an antique car parade joined in the festivities.
The twin bores, which are almost a mile long, were set to open to the public early Tuesday.
The $439 million federally funded project has been decades in the making, as community members fought against an alternative plan to pave a longer road through the adjacent rolling and scenic inland hills.
The project is named after the late Rep. Tom Lantos, who secured much of the funding.
"I only wish that Tom was also able to see this day come to fruition. His efforts, as well as so many on the coastside, ensured that pristine coastal land was not paved over," state Sen. Leland Yee said.
The tunnels are equipped with 32 jet-powered exhaust fans, carbon monoxide sensors and a pair of 1,000-foot bridges. Ten fireproof shelters are staggered between the double bores, and remote cameras dangle from the ceiling, monitored constantly by a staff of 15 people.
"Devil's Slide has been an enormous undertaking in difficult terrain," said Brian Kelly, acting state secretary of the business, transportation and housing agency. "Ingenuity, will, and perseverance combined to get this project done."
Watchdogs are questioning an exclusive agreement between the City of Oakland and a non-profit group, tapped to lead a multi-million dollar project to redevelop the area around the Coliseum BART station.