In 1923, the cities of San Mateo, Burlingame, and Hillsborough began planning a bridge to link the San Francisco Bay peninsula cities with East Bay and Central Valley communities. Even after the Dumbarton Bridge opened in 1927, these municipalities continued pursuing construction of a bridge for the San Mateo area. Construction began in 1928, using cement for the piles and deck slabs from Redwood City and oyster shells dredged from the Bay in the Redwood City area as part of the cement mix. In 1929, after only fourteen months of construction, the bridge was finished ahead of schedule, and the City of San Mateo celebrated the opening of the new $7.5 million, 7 mile-long San Francisco Bay Toll Bridge. During that period, it was considered the longest continual vertical lift highway bridge in the world. During the 1930s, fewer than 2,000 vehicles crossed the bridge daily, but within the next 20 years that number increased to 9,000, prompting civic leaders to consider the need for a new bridge. In 1967, construction of the new San Mateo Bridge was completed, and its higher design eliminated the need for a drawbridge by allowing ships to pass underneath.