The 'Charlie St. Cloud' star has just been on vacation to Hawaii with his younger brother Dylan and the thrill-seeking pair weren't afraid to leap off a 35ft cliff into the ocean when they found a spectacular waterfall.
He said: "I kicked off the summer by taking my little brother, Dylan, on a graduation trip to Hawaii. He's going off to college next year, and I've been working very hard, so we haven't been able to see each other as much as we would have liked to in the past few years. We hiked through the inner jungle in Maui, and you come across these really beautiful spots. We found this hidden place where there was an enormous waterfall and cliff jump. It was about a 35ft drop."
Zac – who shot to fame in the 'High School Musical' movies - insists he is fairly fearless in his life and is the kind of person who likes to convince others to try out crazy things.
The 22-year-old star added to Parade magazine: "Once you've done it, the funny part is trying to convince someone else to jump off, too. I'm the one who's always saying, 'Go for it, go for it - jump!' And then when you come up out of the water, you feel fantastic."