For the sesquicentennial year of the 1867 Alaska Purchase, Juneau-Douglas City Museum asked me to create 3 banners showing 150 years of change. The banners feature oblique views of Juneau, Mendenhall Valley and Auke Recreation beach from the air today. Above each of these view is a retrospective, showing what that same view looked like at the time of purchase, 150 years ago.
I also wrote a 41-page background paper describing methods, historical context, etc: 1867-2017: 150 years of change.