I was in Kyeller ENKJ in 2015 with my Swiss registered taildragger. It was then open for GA and a very nice place with fast metro access to Oslo and much cheaper hotels than the capital. Many compulsary reporting points when approaching from the North due to the vicinity of Gardermoen. However, the people running the airport were worried because Kjeller seems to have lost a maintenance contract of the Norwegian Airforce. But the flying club is still active. Nice place, friendly club.