The intelligent transportation systems use an advanced algorithm to integrate and optimize three types of traffic data, including (1) filtered real-time automatic vehicle identification data; (2) real time video detector data; and (3) offline travel time forecasts. The integrated data is used for real-time estimation of average journey time and traffic speed on selected routes which is updated once every two minutes. This integrated algorithm has been adopted in Hong Kong’s Journey Time Indication System and Speed Map Panel System, which display alternative route journey time and sectional traffic speed colour on traffic sign boards, to help motorists choose the most appropriate routes in order to avoid traffic congestion, and to help transport authorities monitor the traffic conditions for better traffic management.