Using AI to Annotate Vintage Maps

Bosphore 1819 is an interactive version of a beautiful 1819 topographical map of the Bosphorus. The original Plan Topographique du Bosphore de Thrace ou Canal de Constantinople et de ses environs was surveyed by François Kauffer between 1776 and 1786, before being redrawn and expanded by Jean-Denis Barbié du Bocage and published in 1819.

The original map is wonderfully detailed, but navigating it isn't particularly easy - particularly if you can't speak or read French. Hundreds of villages, palaces, fortifications, streams, capes and other landmarks are labelled using French spellings of Ottoman Turkish names. Bosphore 1819 turns all those labels into a database that can be searched using the modern place-names of the region.

There are 387 places mapped in total. Click on any label to see its name as it appears on the original map, its Ottoman Turkish name in both Latin and Arabic script, and the modern name. You can also search for a place using any of these three versions of its name and jump straight to its location on the map.

The map itself is worth exploring even if you aren't particularly interested in historical Istanbul. Zooming into the beautifully detailed engraving reveals a dense historical landscape of settlements, roads, waterways and landmarks. It also isn't oriented north-up: the Black Sea is on the left and the Sea of Marmara is towards the lower right. 

Bosphore 1819 is a great example of how an old scanned map can be transformed into a fully modern interactive annotated experience. The most impressive part of the project may be how the map was transcribed. The 13 MB scan was split into 54 overlapping sections, which were then given to multiple Claude Opus 5.5 agents to read the densely engraved and often curved place names. Each agent recorded the original French spelling, Ottoman Turkish name, modern identification and location of each label, with uncertain readings explicitly flagged. The resulting data was then merged, checked for consistency and overlaid on the map, producing the 387 searchable entries used by the app.

The Source code and data for the map can be viewed on GitHub.

Also See

The Annotated Fra Mauro World Map - an annotated 1450 Venetian map of the world

Annotated Claudius Map - an annotated version of Matthew Paris' 13th Century map of Britain