Lighthouses WorldwideInteractive map of lighthouse signals

Background

OpenStreetMap contains detailed lighthouse and light-signal information, but the raw data is not immediately suitable for a user-friendly map or standardised downstream processing. Different element types, nested tags, numbered light sectors and varying coordinate structures need to be interpreted first.

Users would otherwise have to understand the seamark schema and identify relevant entries manually. Other applications would need to download the full raw response and repeat the same complex transformation. The prepared information also needed to be available outside the map for analyses and automated workflows.

Defined solution

The application provides a searchable global map with filters for light colours and multi-coloured sectors. Detailed signal information includes colour, characteristic, repetition period and the geographic orientation of individual sectors.

The preparation pipeline converts raw Overpass results into a consistent rich dataset. Stable public download links provide both normal and gzip-compressed files. A URL-based handover can send a selected lighthouse to an external detail or receiver application as Base64URL-encoded JSON without an account, database or server-side session.

Outcome & value

Complex maritime source data becomes understandable and directly usable. Visitors can explore signals visually, while developers and analysts can reuse the same prepared dataset. At the time of documentation, the rich dataset contained 18,619 lighthouse and light-signal records.

Technical implementation

GitHub Actions runs the daily retrieval, Python preparation and deployment workflow. The static GitHub Pages application is connected to its domain through Cloudflare, which provides DNS and encrypted HTTPS delivery. The map uses browser-side JavaScript and geographic data formats, so no dedicated application server is required.