The Friday File: The city with the worst traffic is London where the average travel time per 10 kilometers (6.21 miles) is 36 minutes 20 seconds. In second is Bengaluru, India at a time of 29 minutes 10 seconds. Third is Dublin at 28 minutes 30 seconds. New York is 19th at a zippy 24 minutes 30 seconds. London also has the slowest rush hour speed of 14km/hr (8.7 mph).