Hudgens, most recently of "Spring Breakers" fame, 24, and the "Twilight" star, 26, where also joined by Hudgens's boyfriend, Austin Butler.
Hudgens hinted that she was going on a trip in a tweet she wrote on June 18. The post read, "Photo: Going on a lil adventure :)"
Both Hugdens and Greene looked incredibly fit as they surfed Indonesian waves. Asked about how she keeps her body in shape, the "Machete Kills" star told Us Weekly she does a little bit of everything.
"I try to shock the body as often as possible -- I think that's really important," she said. "I do Soul Cycle constantly, do a lot of Pilates, a lot of yoga for the mind, dancing, kickboxing, hiking. . . anything and everything!"
As for how the surfing session went, a photo of Grenne's bruised leg posted on her Instagram account says it all.
"War wound from surfing today with Oakley," the actress captioned the picture. "The reef ate me up. #worthit"