The Manhattan Bridge was constructed by Othniel Foster Nichols. The bridge has two thin "two-dimensional" 322 foot support towers supporting 3224 foot cables. The original design included two decks supporting four lanes of traffic, two subway lines and two trolley lines. The two decks were altered in 1940 to include seven lanes of traffic and four subway lines. The increased weight of these modifications lowered the stability of the bridge and serious degradation was discovered in 1978. Stabilization on the bridge ran from 1985 to 2007.

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