Green Flyway is a cross-border Norwegian-Swedish test environment for drones, U-space services and future zero-emission aviation. Located in the Arctic region between Røros and Östersund, the initiative combines controlled airspace, harsh weather conditions, low traffic density and real-world operational testing. The presentation will share lessons learned from cross-border drone operations, emergency response testing, BVLOS operations, U-space implementation and the transition towards electric and hydrogen-powered regional aviation. It will also present the vision of developing Europe's first operational Nordic corridor for autonomous and zero-emission air mobility.