How did aerial photographs improve mapmaking during World War I?

During World War I, the introduction of aerial photography marked a significant advancement in military engineering and cartography. While terrestrial photogrammetry had been utilized in the decade preceding the conflict, the war saw the emergence of aerial photogrammetry as a vital technique for reconnaissance and map production.1

Aerial photographs improved mapmaking by allowing large areas to be surveyed quickly, capturing details that were often hidden from ground-based cameras. By taking photographs in overlapping strips, military engineers could assemble mosaics and establish a framework of control points based on recognizable terrain features. This process enabled the creation of more accurate maps, as the overlap allowed for the identification and scaling of features relative to known ground-control points.12

Furthermore, these aerial images provided essential intelligence for military operations, serving as a supplement to or a substitute for traditional topographic maps in areas where detailed surveys were unavailable. This development laid the foundation for the more sophisticated photogrammetric techniques and equipment that would be further refined in the decades following the war.34