6th Street Bridge before and after

Now you see it, now you don't.

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Demolition work on the 6th Street Bridge in downtown Los Angeles began Feb. 5. Officials say the 84-year-old 6th Street Viaduct — as it is formally known — must be removed because of chemical deterioration in the span's concrete. The demolition is expected to take nine months; a replacement bridge is planned for completion in late 2019. Built in 1932, the bridge was the city's longest, extending about 3,500 feet. (Left: Luis Sinco / Los Angeles Times. Right: Genaro Molina / Los Angeles Times)