Interchanges and intersections Roads 20 Design and construction 5 Express highways 4 Economic aspects 3 Highway capacity 3 Regional planning 2 Traffic flow 2 Traffic safety 2 Bibliography 1 Civil engineering 1 Concrete construction 1 Decision-making 1 Effect on land use 1 Engineering design 1 Environmental aspects 1 Freeways 1 Interchanges 1 Law and legislation 1 Mathematical models 1 Pedestrian areas 1 Right of way (Traffic regulations) 1 Roads, Concrete 1 Roundabouts (Traffic intersections) 1 Traffic accidents 1 Traffic engineering 1 Urban transportation 1