Pei Xiu
Later Chinese ideas about the quality of maps made during the Han Dynasty and before stem from the assessment given by Pei Xiu. Pei Xiu noted that the extant Han maps at his disposal were of little use since they featured too many inaccuracies and exaggerations in measured distance between locations. However, the Qin State maps and Mawangdui maps of the Han era were far superior in quality than those examined by Pei Xiu. It was not until the 20th century that Pei Xiu's 3rd-century assessment of earlier maps' dismal quality would be overturned and disproven. The Qin and Han maps did have a degree of accuracy in scale and pinpointed location, but the major improvement in Pei Xiu's work and that of his contemporaries was expressing topographical elevation on maps.