The N5 Longford bypass has opened after 16 months of construction and an investment of €26 million.
The National Roads Authority (NRA) says it is opening 2 months ahead of schedule and on budget.
The 2.6 kilometres stretch of carriageway includes a bridge spanning the River Camlin and the realignment of local and regional roads.
Transport Minister Leo Varadkar says it will reduce journey times between the Greater Dublin area and Mayo, Sligo and Roscommon by removing a significant bottleneck at Longford.
Sean O’Neil is from the NRA.
He says the bypass is open for business this Bank Holiday weekend.