<P> Signs on the National Highways (G - prefix) are green, while on the lower - grade highways and urban expressways (A-prefix) are blue . </P> <P> In Hong Kong, the type of high speed roads is referred to as expressway, but some are named as highways or roads (' Yuen Long Highway',' Tolo Highway',' Tsuen Wan Road',' Tuen Mun Road', etc .). Some others are named corridors and bypasses . </P> <P> In Colombia are managed by the Colombian Ministry of Transport through the National Institute of Roads . Colombia's road infrastructure is still very underdeveloped with most of the highways presenting a two lane road for outbound and inbound traffic . Some exceptions are the Autopista Norte, linking Bogota and the towns of Tunja and Sogamoso and the Highways of the Valle del Cauca, an infrastructure improvement project started about a decade ago which has not yet been entirely finished . Several dual - carriage ways also link cities like Medellin, Pereira, Manizales and Armenia . </P> <P> Nowadays, the direct public funding on highways is increasing, focused mostly in connecting Colombia's agricultural and industrial heartland with its Caribbean and Pacific ports through twinning existing roads and the construction of 5,892 km of roads . </P>

Who has the best highway system in the world