The Caldecott Tunnel is a four-bore highway tunnel through the Berkeley Hills between Oakland, California and Orinda, California. The east-west tunnel is signed as a part of State Route 24 and connects Oakland to central Contra Costa County and is named after Thomas E. Caldecott (1878–1951), mayor of Berkeley from 1930–1932, member of the Alameda County Board of Supervisors 1933-1945, and president of Joint Highway District 13, which built the first two bores. - Source: Wikipedia