They were installed early last month and now they're being tested.
The new lighting system on the Jacques Cartier bridge, at a cost of some $40,000,000, is being tested.
Tube and projection lights are featured on the supports as well as the bridge interior, and the turrets.
The plan is for changeable lighting on the span to suit wind, traffic, the colour of the sky, and for special events.
Wiring the bridge will need more than 10 km of cables and 10,000 separate mounting systems.
The lighting coincides with Montreal's 375th anniversary this year.
-With files from CTV News