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Charlize Theron

Charlize Theron is dating again after finding romance with "a really cool dude", who took her on a midnight hike.

The 41-year-old, who broke off her romance with Sean Penn just over a year ago, is refusing to name her new guy, but told radio host Howard Stern he's not famous.

"I went on a date maybe, like, a month ago," she told Stern on Wednesday. "I had a great date, I've got to tell you. I had an incredible date. This guy really impressed me.

"We went for a nine-mile hike in the middle of the night. It was a full moon. But I was really impressed. It was fun.

"I'm not going to say where we met, but we ended up going for a walk... It was just really fun. He was super funny. I think he's just a really cool dude. It was super private... That's what made it so much fun, too."

The actress was recently linked to Halle Berry's ex, Gabriel Aubry, after the couple was spotted hanging out at Santa Monica Pier in California at the end of May, but that could just have been two parents enjoying an evening out - Theron's six-year-old son Jackson attends the same school as Aubry and Berry's daughter Nahla.

Apart from actor and filmmaker Penn, Charlize has dated Stuart Townsend and rocker Stephan Jenkins, and she has been romantically linked to Seth MacFarlane, Alexander Skarsgard, Jeremy Renner, and her Sweet November co-star Keanu Reeves.