It took more than 70,000 tonnes of concrete and 2.5 million hours of work to complete but the New Ross Bypass will finally open to traffic at noon tomorrow.
The scheme includes Ireland's longest bridge, the Rose Fitzgerald Kennedy Bridge, which sits 36 metres above the River Barrow.
The bridge is part of the N25 New Ross Bypass, delivered by the BAM/ACS consortium on behalf of Transport Infrastructure Ireland (TII), and Wexford and Kilkenny County Councils.
It aims to cut peak journey times by up to 30 minutes on the N25 between Cork and Rosslare.
The new road includes Ireland's longest bridge, measuring some 887 metres, crossing the River Barrow between counties Wexford and Kilkenny and it is named in honour of the mother of John F Kennedy, Rose.
Rose Katherine Kennedy Townsend, a great-granddaughter of Rose Fitzgerald Kennedy, was present for the official opening of the bridge which, she said, is a fitting tribute to her family.
"This bridge is a wonderful tribute to my great grandmother, and a symbol of her enduring love and lesson that it doesn’t matter who you are, where you come from, we are all God's children," she said.
The bridge was built with the same amount of reinforced steel as the Eiffel Tower and includes some 500km of cabling wire, similar to the length of Ireland. The bridge's two main spans are the longest post-tensioned concrete spans of their type in the world.
An Taoiseach Leo Varadkar attended the official opening.
"By reducing congestion and travel-times, improving road safety, and opening up economic opportunities, this will make a huge difference for commuters, for families, for businesses and for tourists," he said.
The 35th president of the United States, John F Kennedy’s ancestors hail from Dunganstown, Wexford. The Kennedy homestead is less than one mile from the new bridge.
President Kennedy visited his family town of New Ross in the summer of 1963.
The late president’s sister, former US ambassador Jean Kennedy Smith suggested the bridge be named after their mother, in memory of the entire extended family.