# Poland map boundary data

Boundary data: OpenStreetMap contributors / Wambacher, distributed by geoBoundaries.
Dataset: POL-ADM1-17162690, 16 first-level administrative units (voivodeships).
Source geometry year: 2017. geoBoundaries build: 12 December 2023.

Source: https://github.com/wmgeolab/geoBoundaries/tree/c0ed7b8dc62dabe97cf355622f557ccfe8546f2b/releaseData/gbOpen/POL/ADM1

The original source topology is available alongside this file as
[poland-boundaries.topojson](./poland-boundaries.topojson).

The boundary data and derived boundary geometry in `lib/poland-map.ts` are available
under the Open Data Commons Open Database License 1.0:
https://opendatacommons.org/licenses/odbl/1-0/

Copyright and attribution: https://www.openstreetmap.org/copyright

Changes: projected coordinates into a 530 × 500 Web Mercator SVG viewport,
simplified shared boundary arcs with a 0.35 viewport-unit tolerance, rounded SVG
coordinates to two decimal places, and styled the resulting map for this website.
City positions come from the e-Nekrologi directory and verified cemetery sources and use the same projection.