It’d be easy to pass her oƒff as just another foreign supermodel who made it on gorgeous features and a fit physique alone.

But nearly 10 years ago, Petra Nemcova was in the grips of hell in Thailand, clinging to the limbs of a tree with a broken pelvis as the great waves of 2004’s Indian Ocean tsunami demolished everything around her. Over the course of eight hours, the Czech model and five-time Sports Illustrated swimsuit issue alumna lost her fiancé to the sea and came close to the cusp of emotional and physical surrender—but she didn’t break.

The following year, inspired by the tragedy, she founded the Happy Hearts Fund, a nongovernmental organization that rebuilds schools in countries devastated by natural disasters. Today, Nemcova, who speaks five languages and has taken marketing and finance classes at Cambridge and London Business School, is an adrenaline junkie who loves to find fun ways to stay active while getting in touch with the very natural world that almost killed her.

So, what—dare we even ask—does it take to impress one of the strongest, most beautiful women we’ve ever met?

“Healthy confidence,” Nemcova says. “Sometimes people have a confidence that’s sort of shallow; but if you know who you truly are—not just from a physical or mental standpoint, but also on a deep-searching level—it gives you a confidence that’s very attractive. That’s a huge attraction for me, and I think for many women."

“If you’re giving yourself away as someone you’re not,” she says, “you’re wasting your time."