Carquinez Strait Powerline Crossing

Carquinez Strait Powerline Crossing was the world's first powerline crossing of a large river. It was built in 1901 for a 60 kV powerline operated by Bay Counties Power Company to deliver electric power to Oakland, California. For this a crossing of Carquinez Strait was required, which has at its narrowest point a width of 1 kilometre (0.62 mi). Such a span width was impossible with wooden poles, which were common in those days. Installing an underwater cable was considered, but for reliability reasons an overhead powerline was installed, which used at the north site of the river a 68 metres (223.10 ft) tall lattice tower and at the south site one with a height of 20 metres (66 ft).