And they're off! More than 14,600 people will run through the streets of the capital today for the SSE Airtricity Dublin Marathon.
There are over 10,000 Irish entrants and the good news is that the weather looks favourable for the event.
Met Eireann said it will be a cloudy, breezy and mild day.
There will be some good dry intervals in most parts of Leinster, although some parts will see scattered outbreaks of rain and drizzle during the course of the day, with temperature highs of 14 to 17C.
The course itself is largely flat and is a single lap, starting and finishing close to the city centre.
The first participants set off at 8.50am and rolling traffic restrictions will follow along the route. Race and traffic details can be found at www.dublinmarathon.ie
The 42km (26.2 mile) route starts at Fitzwilliam Street Upper and ends at Merrion Square.