Romania opens 5.9-kilometre Comarnic bypass to relieve DN1 traffic bottlenecks

Traffic opening on the DN1 corridor

Authorities opened the Comarnic bypass to vehicular traffic at 14:00 on Thursday, 1 October 2026. The 5.9-kilometre road provides an alternative route around the town of Comarnic in Prahova County, diverting transit and heavy vehicles away from the urban centre. The route connects to national road DN1, a corridor through the Prahova Valley that frequently experiences traffic bottlenecks during weekend travel toward mountain resorts.

National road authority CNAIR director general Cristian Pistol addressed motorists ahead of the opening.

Have a pleasant weekend in the mountains, this time without the mandatory stop in Comarnic.

Construction timeline and project costs

Construction on the bypass began in November 2023 under then transport minister Sorin Grindeanu. At the time work commenced, then Prahova County Council president Iulian Dumitrescu expressed hope that traffic could use the route within one year. Completion took nearly three years following project approval under a December 2022 partnership between CNAIR and the Prahova County Council.

Initial execution costs stood at 340 million lei, but authorities supplemented funding by roughly 130 million lei in 2025 to address route modifications and terrain landslides. Sources report differing overall totals: Prahova County Council president Virgiliu Nanu stated the project reached 516 million lei, including 438 million lei for construction and assembly. CNAIR reported a total investment of 470.06 million lei with value-added tax under the 2021–2027 Transport Programme. The construction tender was awarded to a consortium led by SC Frasinul SRL alongside SC Artehnis SRL for 236.74 million lei excluding tax.

Technical specifications and structures

The bypass incorporates four intersections controlled by roundabouts to regulate entry and exit points, along with two short-stay parking areas positioned on each side of the carriageway. Multiple complex structures carry the roadway across existing natural and transport corridors.

According to technical data from local and road authorities, the route features two bridges spanning the Prahova River, measuring 81 metres and 40 metres in length. A central viaduct spanning 370 metres (described as approximately 380 metres by the county council) features nine spans that clear the Prahova River, the Bucharest-Brasov railway main line, and Podului Neag street. Cristian Andrei, an official at CNAIR, confirmed the completed alignment meets high traffic safety standards.

Traffic expectations and regional connections

Infrastructure specialists note that the bypass serves primarily as a relief corridor rather than a full solution to Prahova Valley congestion. Ionuț Ciurea, executive director of the Pro Infrastructură Association, pointed out that roundabouts connecting to local roads will still create conflict points between transit drivers and local residents, with the most noticeable time savings occurring outside peak hours.

The good part is that this bypass is an alternative, an extra road that will divide traffic, both transit and local. The less good part is that it only partially solves the traffic problem.

Ciurea stated that full resolution of congestion along the corridor requires building a motorway, projecting that machinery could appear on that project by 2030. Local officials consider the new bypass complementary to the planned A3 Ploiesti-Comarnic-Brasov motorway, which is designed to include a dedicated junction in the Comarnic-Breaza area.