A 1913 Oakland christens the new Devil Slide Tunnel in San Mateo County CA (just South of SF). The 4,200-foot twin-bore tunnel is the first highway tunnel in California in nearly 50 years and a state-of-the-art project that will eliminate a dangerous stretch of highway known for collapsing in wet weather. Caltrans will block off the troublesome 1.1-mile stretch of Highway 1, build parking lots at either end and hand it over to San Mateo County, which will turn it into a hiking and biking trail with a great view. Motorists will have less of a view as they zip through the one-lane bores, but they'll have a safer trip, and some assurance that the highway won't collapse as it has repeatedly since it opened in 1937.

Source: sfgate.com