Police shut Skerton Bridge, which carries the southbound lanes of the A6 over the River Lune into the city centre, at around 5.45am.
Police advised people to 'avoid the area where possible', whilst emergency services worked at the scene.
But the incident was safely resolved and the woman is now in the care of the emergency services.
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A police spokesman said: “It was a concern for safety involving a person on the bridge.
“She is in the care of emergency services and safe.
“The road has reopened.”