The award-winning actor was barred from Maccarthy's Bar in Castletownbere while filming a series there aged 19.
Publican Adrienne Maccarthy has since lifted the barring order, after making amends with Farrell when he returned to the area to film Ondine in 2009.
Speaking to The Echo, Adrienne recalled the actor's “outrageous” behaviour while he was in Castletownbere filming Falling For A Dancer in 1998.
“Anyone who is barred doesn’t remember afterwards which is handy for them,” she joked.
She also spoke of her pride while watching Farrell's career go from strength to strength over the years, adding: "We’ve watched Colin grow up and while his behaviour was outrageous back then, he was just young and enjoying life".
Farrell recently returned to the area with his son, who opted for a trip along the Wild Atlantic Way when given the choice between the rugged route and a road trip across America.
The pair paid a visit to Maccarthy's while on their travels, spending time with Adrienne and the pubs' beloved pet pug.
"He is very normal and down to earth", Adrienne said.
"He doesn’t boast or brag. No matter what happens it won’t change him. His feet are always on the ground and he will never lose his footing.
“It’s crazy to think that his oldest son is the same age he was when we had to barred him from the pub. We just laugh about it now".
Header image via Facebook/Maccarthy's Bar