If you don't mention this epic radio phone call on Father's Day, are you even celebrating Father's Day?

The infamous phone call happened more than 10 years ago but it still does the rounds on social media every year around this time.

The clip is originally from "Reverse Trial" show, when host Gareth Lischner tried for nearly two minutes to get caller Solly to say the question which was, in fact, the answer: "What day is Father's Day?"

Now a radio manager with NZME, Gareth told Simon and Phil it's still surreal how viral the clip went, and he still gets a bit of stick when it does the rounds every Father's Day. 

LISTEN ABOVE