1928- aerialphotographs aerialphotography aerialreconnaissance aerialsurveys antiquities archaeology artificialsatellitesinremotesensing congresses england essex excavations(archaeology) exhibitions georg gerster greatbritain historicsites jordan landscapearchaeology landscapes maps methodology nationalmappingprogramme(greatbritain) photographicinterpretation prehistoric prehistoricpeoples remotesensing socialscience spacephotography