The Three Sisters

2013-03-24-Three-Sisters-01

Supposedly Pittsburgh is the only  place in the world where you can see three identical suspension bridges in a row: the Sixth, Seventh, and Ninth Street Bridges over the Allegheny, now named for Roberto Clemente (because the Sixth Street Bridge leads to the ball park), Andy Warhol (because the Seventh Street Bridge leads to the Andy Warhol Museum), and Rachel Carson (because we’re really proud of Rachel Carson).

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3 thoughts on “The Three Sisters

  1. Father Pitt – these bridges are doubly rare – not only are they identical in design, but the design itself is extremely rare. These are self-anchoring suspension bridges. In most suspension bridges – like the 10th street bridge, the suspension cables are anchored to the ground. But that takes room, which is one reason why Pittsburgh has very few suspension bridges. On these bridges, the cables are anchored to the deep trusses that separate the roadway from the walkways. In essence, the dead-weight of the truss puts tension in the cables, and the bridge suspends itself. They were built in 1928, based on a German prototype, and I don’t know of any others like them.

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