DN1 (Drumul Naţional 1 in Romanian) is an important national road in Romania which links Bucharest with the northwestern part of the country. On the Bucharest - Ploieşti section, traffic jams appear very often due to the fact that DN1 serves both Bucharest's airports (Henri Coandă International Airport (Otopeni) and Băneasa) and the touristic region of Valea Prahovei (Prahova Valley).
The segment of DN1 that serves the area north of Bucharest was upgraded at the end of 2005; it now has three traffic lanes on each side and two new interchanges at Henri Coandă airport and Otopeni bridge. Although it doesn't complete the motorway specifications, the DN1 road can be considered an expressway on certain segments. A modern CCTV system has also been installed on the section from Bucharest to Sinaia to prevent speeding and accidents.
It is to be made obsolete by 2013 by the A3 Transilvania motorway.
The main cities linked by DN1 are Bucharest, Ploieşti, Braşov, Sibiu, Alba Iulia, Cluj-Napoca, Oradea.
