Mark Tully writes with a link to the above video, part of the Visualizing Early Washington DC project, which I’ve seen before but (as has sometimes happened) I never seem to have gotten round to posting it. Here’s a description of the project:

UMBC’s Imaging Research Center (IRC) is working to re-create Washington DC in its early years 1790-1820. Remarkably little visual information remains from this time period. What began as a simple effort to use 3D digital re-creation and display techniques has become full-scale research to uncover the original landscape. In 1791, Pierre-Charles L’Enfant arrived in Georgetown Maryland with orders from President George Washington to lay out the new Federal City. What did he actually see as he rode the land on horseback? This is just one question that we are trying to answer.