Bosphore 1819: A searchable, annotated version of an 1819 Bosphorus map

# What this map is Bosphore 1819 is an interactive version of Plan Topographique du Bosphore de Thrace ou Canal de Constantinople et de ses environs, a detailed topographical engraving published in 1819. The original survey work was carried out by François Kauffer between 1776 and 1786, and the map was later redrawn and expanded by Jean-Denis Barbié du Bocage before publication.

The original plate is densely labelled in French spellings of Ottoman Turkish place-names. That makes it hard to use unless you read French and can match old spellings to modern names. This project turns those labels into a database that you can query with modern place-names.

# How the map was transcribed The map started as a single 13 MB scanned image. To make transcription practical, the scan was split into 54 overlapping sections. Each section was processed by multiple Claude Opus 5.5 agents, which read the engraved and often curved place-names.

Each agent recorded four pieces of information for every label it could read: the label as printed on the original map (French spelling), the Ottoman Turkish name rendered in Latin script, the Ottoman Turkish name in Arabic script, and the modern place-name identification. When an agent had low confidence about a reading, that uncertainty was explicitly flagged. After agent passes, the separate outputs were merged and checked for consistency before they were overlaid on the map.

This workflow produced 387 mapped place entries that power the interactive search and popups.

# What you can do on the site

• Click any label on the map to view: the original French label, the Ottoman Turkish name in Latin and Arabic script, and the modern name used for identification.
• Search for a place using any of the three name forms and jump directly to its mapped location.
• Zoom into the engraving to explore a dense historical landscape of settlements, roads, waterways, palaces, fortifications and other landmarks.

Note the map's orientation: it is not north-up. The Black Sea appears on the left side of the image and the Sea of Marmara is toward the lower right.

# Data and reuse The project publishes its source code and the underlying data on GitHub. That lets researchers, historians, map enthusiasts and developers inspect the transcriptions, review flagged uncertainties, and reuse the dataset for their own projects.

# Practical takeaways for researchers and map users

• The dataset provides a direct link between 19th-century French map labels and modern place-names, with Ottoman script included for comparative study.
• The transcription workflow combines automated agent reads with manual consistency checks and explicit uncertainty flags, which helps users judge reliability for individual place identifications.
• If you plan to reuse the data, start by reviewing entries flagged as uncertain in the GitHub dataset.

# Quick navigation tips

• Use modern place-names when searching to find entries quickly.
• If a search result looks uncertain, open the item to compare the original French label and the Ottoman script reading before citing it.

Bosphore 1819 converts a visually rich historical engraving into a practical, searchable resource while keeping access to the original printed labels and making transcription choices visible.