Twiggy, born Lesley Hornby, was one of the defining faces of London’s Swinging Sixties and is widely considered to be one of the world’s first supermodels.At 15, she met a hairdresser named Nigel Davies (now known as Justin de Villeneuve), who gave Hornby her signature boyish haircut. Davies called the then-teenager Twigs because of her waifish frame, though it was a 1966 article in the Daily Express that described her as Twiggy.Twiggy was initially known for her thin build (thus her nickname) and the androgynous appearance considered to result from her big eyes, long eyelashes, and short hair. She was named “The Face of 1966” by the Daily Express and voted British Woman of the Year. By 1967, she had modeled in France, Japan, and the US, and had landed on the covers of Vogue and The Tatler. Her fame had spread worldwide.After modeling, Twiggy enjoyed a successful career as a screen, stage, and television actress. Her role in The Boy Friend (1971) brought her two Golden Globe Awards. In 1983 she made her Broadway debut in the musical, My One and Only, for which she earned a Tony nomination for Best Actress in a Musical.On Sept. 19, the supermodel celebrates her 70th birthday. As our way of showing our appreciation for Twiggy’s effect on the fashion world, we collected a gallery of 30 fascinating photos of a young Twiggy in the late 1960s.