St. George's Church in historic downtown Madaba, also known as the Map Church, was constructed in the late 19th century over the site of a sixth-century Byzantine church, thus protecting much of the original mosaic floor. Preserved in the mosaic was the earliest known map of the Holy Land, most likely designed to guide Christian pilgrims as they visited sacred sites throughout the region. Its uniqueness is one of the reasons tourists visit Madaba in numbers second only to Petra in some years.