It's taken six years to build and is six times the length of Dublin's O'Connell St. The north runway has also been completed and opened on-time and on budget.
Flight FR1964 took off shortly after midday.
It will provide extra capacity for growth and the creation of over 30 thousand jobs.
North Runway at Dublin Airport is officially open...
Ryanair flight FR1964, bound for @EINairport, took off shortly after 12 noon off 28R in a westerly direction.
A proud moment for all of the team at Dublin Airport and daa. pic.twitter.com/yBkbxQgenK
— Dublin Airport (@DublinAirport) August 24, 2022
Kevin Cullinane is group head of communications with DAA.
"This gives us extra capacity, which means we will have one runway for departures and one for arrivals." Mr Cullinane said.
"In the short term there will not be any additional flights, but it does mean it will over the coming weeks, months and years ahead allow us to fly direct to more long haul destinations, due to the length of it."
