airport. It is situated only north of the Bucharest city centre, within city limits. Roads Bucharest is a major intersection of Romania's national road network. A few of the busiest national roads and motorways link the city to all of Romania's major cities, as well as to neighbouring countries such as Hungary, Bulgaria and Ukraine. The A1 to Pitești, and from Sibiu to the Hungarian border, the A2 Sun Motorway to the Dobrogea region and Constanța, and the A3 to Ploiești all start from Bucharest. A series of high-capacity boulevards, which generally radiate out from the city centre to the outskirts, provides a framework for the municipal road system. The main axes, which run north–south, east–west and northwest–southeast, as well as one internal and one external ring road, support the bulk of the traffic. The city's roads are usually very crowded during rush hours, due to an increase in car ownership in recent years. In 2013, the number of cars registered in Bucharest amounted to 1,125,591. This results in wear and potholes appearing on busy roads, particularly secondary roads, this being identified as one of Bucharest's main infrastructural problems. A comprehensive effort on behalf of the City Hall to boost road infrastructure was made, and according to the general development plan, 2,000 roads have been repaired by 2008. The huge number of cars registered in the city forced the Romanian Auto Registry to switch to 3-digit numbers on registration plates in 2010. On 17 June 2011, the Basarab Overpass was inaugurated and opened to traffic, thus completing the inner city traffic ring. The overpass took five years to build and is the longest cable-stayed bridge in Romania and the widest such bridge in Europe; upon completion, traffic on the Grant Bridge and in the Gara de Nord area became noticeably more fluid. Water Although it is situated on the banks of a river, Bucharest has never functioned as a port city. Other Romanian cities such as Constanța and Galați serves as the country's main ports. The unfinished Danube-Bucharest Canal, which is long and around 70% completed, could link Bucharest to the Danube River, and via the Danube-Black Sea Canal, to the Black Sea. Works on the canal were suspended in 1989, but proposals have been made to resume construction as part of the European Strategy for the Danube Region. Culture Bucharest has a growing cultural scene, in fields including the