The visited-area boundaries on the Expat Life map use these sources:

• Salzburg: Austria’s municipality boundary service, © BEV 2017. The municipality polygon was converted to GeoJSON.
• Bratislava: Slovak administrative boundaries, © GKÚ Bratislava, CC BY 4.0. The 17 city borough boundaries were reprojected and merged into one outline.
• Corinth: 2021 Greek municipal units, ELSTAT / TEE. The Corinth municipal unit was converted to GeoJSON.
• Messinia and Argolida: Greek regional-unit boundaries, NECCA. Both regional units were converted to GeoJSON.
• Other visited regions: Natural Earth administrative boundaries.
• New York City and Princeton: 2025 US Census place boundaries.

The base-map providers are credited in the map’s attribution control.