Why Sophia Loren Can’t Believe She’s in Her 80s!

When Sophia Loren entered her first beauty pageant at the age of 14, color television was still two years away from hitting the airwaves.

At the time, Loren could never have imagined she would go on to become one of the greatest foreign actresses of all time and an international sex symbol, let alone that she would one day be able to look back on her incredible career as an 81-year-old grandmother.

“When you are 20 years old, you don’t think that you will turn 80, but when you do, you still can’t believe it,” the Oscar winner tells PEOPLE.

“My God, so many years went by, wow! I started when I was 15 years old, I was a little skinny little toothpick and then I grew and grew and grew!” she laughs.

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Loren finished as a finalist in the Miss Italia 1950 contest, and later enrolled in acting classes. She soon landed a bit part as an extra in Mervyn LeRoy’s Quo Vadis, which launched her career as a professional actress.

Before rising to international fame after signing a five-picture contract with Paramount Pictures in 1958, Loren worked on a series of films with Italian star Marcello Mastroianni. Despite going on to work with a myriad of legendary Hollywood heartthrobs like Cary Grant and Clark Gable, Loren says Mastroianni will always remain closest to her heart.

“The most charming was Marcello Mastroianni,” she says. “He was somebody who was unique in my career because I worked with him for 20 and more years of my life.

“So he was like my brother, he was like my husband; he was like everything for me. We knew each other so well and we worked together in such a wonderful way. We did one picture after another, and each one was a big success.”

Loren is currently wrapping up an 11-city U.S. stage tour called An Evening with Sophia Loren, during which fans can listen to and ask questions about the film icon’s storied career.