Transport for Denver, US
HTTP CORS ? Free
RTD
API Endpoint
http://www.rtd-denver.com/gtfs-developer-guide.shtmlMore Transportation APIs
Access real-time and historical data of any and all airborne aircraft
HTTPS CORS ? Free
Real-time port congestion risk scores, ETA delays and waiting vessels for 15 global ports
HTTPS CORS apiKey
Get name and website-URL for airports by ICAO code
HTTPS CORS ? Free