As a civil engineer with leading German construction companies, Horst Barow has built highways and bridges in many parts of the world. Having retired he studied history of the antiquity with emphasis on the Roman period. After his graduation he decided to make the study of Roman roads and bridges his special interest, and he systematically collected material and surveyed bridges on the spot.
Friedrich Ragette spent about 30 years teaching and practicing in the Middle East. The past couple of years he was professor of architecture at the American University of Sharjah.