From the 1860s to the 1880s two explorers - the German Teobert Maler and the American Edward Thompson - competed in a bitter rivalry to find and photograph lost Mayan cities, deep in the Mexican and Guatemalan jungles. Maler was the superior scientist and photographer, but Thompson had a flair for adventure and self-promotion - and a way of keeping his discoveries out of government hands. Between them, they rediscovered a wonderful lost civilisation, whose language and architecture still challenges today's hi-tech archaeologists. Teobert Maler died embittered and almost forgotten; but his photographs are still treasured as the first and best records of Mayan cities before they were overrun by tourists from the developed world.