A palimpsest is a page scraped down and written over, where the older text still bleeds through. A city is the same thing. This is a live modern map with historical maps georeferenced and layered beneath it, so you can pull one slider and watch a place become what it used to be.
Honest stage: this one is early — right now it's the plan, the vetted map sources, and this page. No live map is running yet, and nothing has been georeferenced. I'm sharing the vision to find the people who'd want to walk their own city back through time.
Open a place you know. Under today's streets sit the same blocks in 1950, in 1900, in the 1850s — real historical maps warped onto real coordinates, not decorations. Drag the time dial and the present dissolves into the past: a rail yard becomes a park, a shoreline walks inland, a street remembers its old name. The old map shows through the new — that's the palimpsest.
A live vector base map (MapLibre) of the present, so every old layer has real coordinates to sit on.
Historical scans warped onto those coordinates using open standards — the IIIF Georeference extension and Allmaps — so a 19th-century drawing lands on the exact modern spot.
A single time-slider that cross-fades the layers, plus per-layer opacity, so the palimpsest effect is something you control, not a fixed picture.
Start where the coverage is already dense and already georeferenced — the first demo is one U.S. city (New York, via the NYPL Map Warper, is the front-runner), with layers around 1850, 1900, and 1950.
No license, no layer. The plan draws only from open and properly-licensed collections: Allmaps and the NYPL Map Warper for georeferenced scans, the David Rumsey collection and the Library of Congress for public-domain maps, and OpenStreetMap / Protomaps for the living base. Nothing gets layered in that isn't cleared to be there.
The film is the door for the classics; the map is the door for a place. You may never open a 19th-century atlas — but you'll drag a slider over the corner you live on, and arrive at the history from the side, where it's alive.
If you'd walk your own city back through time — or you work with maps, archives, or local history — tell me where you'd start. The first places built will be the ones real people are waiting for.
Name a city →