A case taken by An Taisce challenging planning approval for the N86 road from Dingle to Camp has been dismissed.
Mr Justice Robert Haughton delivered his judgment at the Commercial Court this morning.
Kerry South TD Brendan Griffin has welcomed the ruling and is hopeful that work will start as soon as possible.
The 65 million euro scheme in West Kerry, which was previously the subject of an extensive oral hearing, seeks to straighten and improve the road from Dingle to Annascaul and from Gortbreagoge to Camp.
An Taisce challenged a decision by An Bord Pleanala to give the green light to the scheme.
The environment and heritage group said the route is renowned for its scenic quality and heritage and sought to have the decision by the planning appeals board quashed.
The challenge was defended by An Bord Pleanala and Kerry County Council.
However, Mr Justice Robert Haughton has today dismissed this.
Charles Stanley Smith from An Taisce has told Radio Kerry news that they wish to thank Mr Justice Haughton for his thoughtful consideration.
An Taisce and its legal team are currently examining the judgement and say it is too early to say whether it will appeal the ruling.
The group has 14 days in which to lodge that appeal.