I took similar photo a few years back with a Canon 7D but with a black sky as I was having dinner with friends and missed the blue hour. When I switched to a M43 system, I didn't have the wide angle lens to do this shot and recently I have acquired a wide angle so I came back to capture this scene. Should try to put on a 10 stop ND filter during the day and the result will surprise you. It certain did for me as I have tried it. I'll keep it myself what was the result so I let you experiment. I cannot spoil the joy of discovering something interesting about photography.
This was taken on the bridge above the Cahill express way. Just opposite The Art Gallery of NSW, and there's more photos if you look close enough with a different angle. Still you can get a light trail effect.