Motorists were forced to swerve around the bird as it sat on the left hand lane of Wester Hailes Road, at around 9.45am on Saturday.
Traffic heading in the direction of the Odeon Luxe cinema was slow moving as drivers tried to avoid the creature.
Katie Owens, 37, from Baberton, pulled in and alerted the police.
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Ms Owens said: “The beautiful bird was just sitting there; I couldn’t pass by.
“I was worried it was injured, but it soon became clear it was not.”
Police Scotland was quick to attend the scene and officers helped passers-by try to encourage the bird towards the neighbouring Union Canal.
Eventually an off-duty SSPCA officer grabbed the swan and released it back in the water.