openaip

https://gpsjam.org/

Maps of likely GPS interference, based on aircraft reports of their navigation system accuracy.

https://notaminfo.com/international

Aeronautical chart from OPENAIP

openflightmaps aeronautical chart

SkyVector - Aeronautical Charts

Opentopomap

Openrailwaymap

Openseamap

Openstreetmap

Google Airports D A CH

Forest chart from DLR

https://www.ead.eurocontrol.int

NOP - Network Operations Portal

Flight information region (FIR/UIR) charts - 2022

https://notaminfo.com/international

Austria

Belgium

Bosnia and Herzegowina

Bulgaria

Croatia

Czech Republic

Denmark

Estonia

Finland

France

Germany

Greece

Hungary

Iceland

Ireland

Italy

Latvia

Lithuania

Luxembourg

Moldava

Montenegro

Netherlands

Northmacedonia

Norway

Poland

Portugal

Romania

Slovak Republic

Slovenia

Spain

Sweden

Turkey

United Kingdom