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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. Bore 1 (the southernmost bore) and Bore 2 were completed in 1937 and are 3,610 feet (1,100 m) in length. Both carry two lanes each of eastbound traffic. Bore 3, completed in 1964, is 3,771 feet (1,149 m) in length. Bore 4 (the northernmost bore), completed in 2013, is 3,389 feet (1,033 m) in length. Bores 3 and 4 carry two lanes each of westbound traffic. All four bores cross the Hayward Fault Zone. ==History== In the 19th century, traffic over the Berkeley Hills in this area went up Harwood Canyon, now known as Claremont Canyon (behind the Claremont Hotel). The road leading up the canyon from the west was initially called Harwood's Road, later changed to Telegraph Road, and finally, Claremont. The road on the other side of the hills was, and remains, Fish Ranch Road. An inn and stage coach stop called the Summit House once existed at the summit. The idea of a tunnel through the hills began as early as 1860. In that year, the idea was proposed and rejected by the citizens of Alameda and Contra Costa Counties. It was revived in 1871 with a proposal which described a route running from the end of Broadway, similar to the actual routing of today's Caldecott Tunnel although it is not clear from the description exactly which canyon was being referred to. The proposed tunnel would be only some 500 feet long and would have its outlet in the San Pablo Creek watershed with a road leading into Lafayette. A franchise was granted to a group of developers who passed the franchise onto another group. The proposal languished until the turn of the century. In 1903 a tunnel was finally built above the present location of the Caldecott Tunnel, in the next canyon south of Claremont Canyon. This tunnel was approached by a new road dubbed "Tunnel Road" which started at the top of Ashby Avenue in Berkeley. The west end of the tunnel was at about while the east end of the tunnel is now in private property owned by the East Bay Regional Park District, on the former site of the Canary Cafe. This tunnel was known as the Kennedy Tunnel, the Inter-County Tunnel or the Broadway tunnel. The tunnel was very narrow and arched, such that two tall buggies could not pass each other. A system of lighting a small fire with a newspaper was used to control this one-way traffic. The tunnel height was increased in 1915 by 3 feet to accommodate larger vehicles.〔(【引用サイトリンク】 title=Lafayette: A Pictorial History )〕 When the new Caldecott tunnel was completed, the Kennedy tunnel was used mostly by pedestrians until it was sealed in 1947.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Caldecott Tunnel」の詳細全文を読む スポンサード リンク
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