RYANAIR Summer flight sale from £4.99 one way!
Cheapest I found was: London stanstead to Denmark £4.99 each way.
Just log onto the website and try which airport and destination that suits!
Terms are quite vague:
Terms and conditions apply. Subject to availability. Fares one way.
Ryanair holidays: Packages include return flights and hotel stay. Booking period: 04.04.18 -29.04.18. Travel period April – May 2018. The price was correct and available on 06.04.18.