The investigation of historical maps is fundamental to understanding the dynamics of landscape changes. In this study, we propose Web GIS tools as a way to compare historical maps efficiently for knowledge production. A key impetus of this article is to contribute to the ongoing efforts to broaden the appeal of ‘mixed‐methods research’ by bridging the epistemological and methodological gaps between GIS and qualitative methodologies in knowledge production. This article proposes a new visualization method for historical landscape change analysis by comparing multiple maps simultaneously with the mash‐up of Web GIS. Based on the analysis of exterior facts represented on the maps, four developmental footprints were investigated, namely, surviving place identity, disappeared place identity replaced by new identity, waning place identity overlapped with new identity, and waning identity by disconnected spatial relationships. To this end, the study argues that Web GIS applications have more potential in spatial knowledge production than traditional desktop GIS.