Centenarians — people 100 years or older — are a rarity. Their lives are often scrutinized as holding the key to aging.

Czech photographer Jan Langer’s portrait series "Faces of Century" shows them in a different light: as human beings aged by years of experience, but at their deepest level, unchanged by the passing of time.

In the series, Langer juxtaposes his portraits with another portrait of the subject from decades earlier. He recreates the original pose and lighting as closely as he can — he wants us to see them not just as they are now, but how they have and haven't changed over time. That is the key to the series.