The event, in its 40th year has taken place with over 20,000 runners.
Some were refused entry to the race due to high interest.
Arklow woman Mary Nolan Hickey was among those who took part, she ran the entire coast of Ireland to fundraise for the RNLI last year.
She completing the same journey on a bike.
Mary, who is the only woman to have run every single Dublin City Marathon since it began in 1980, set out on her latest challenge on the 14th of April.