To travel Europe the airline I like most is definitely Ryanair! There are several low cost airlines of course, like Germanwings, Easyjet, Wizz, etc., but you can’t fly cheaper than by traveling with Ryanair. You sometimes can get from some places in Germany to London, England for as low as twelve Euro including all tax and fees. Of course, that’s a deal you can’t get every day, but anyway, they really do offer great prices around the year.
If you miss the big deals, take a look at regular prices. If you book in advance (one or two months usually should be enough), you almost always can find Germany-London for 40 Euro return. Sometimes a little bit more, sometimes really expensive. But as long as you’re a little bit flexible in your plans, you should get some great results. I would always recommend to start your European travels with Ryanair in London. They fly to so many places from there – you can’t compare it to the destinations you can choose from in Germany.
In May 2015 I for the first time did a „flight trip“ instead of a road trip. Germany, Riga (Latvia), Oslo (Norway), Manchester (England), Dublin (Ireland), and back to Germany. I booked my flights pretty late, but still I only paid about 160 Euro in total – for five flights! That’s about 32 Euro per flight and therefore a great offer to travel Europe!
Still, there might be one disadvantage: the airports sometimes are really far away from where you want to go. For example Frankfurt-Hahn in Germany has nothing, no, absolutely nothing to do with Frankfurt. Actually, by car you would need about 1.5 hours to get to Frankfurt – without traffic. Otherwise, calculate at least two hours. If you choose to go to Oslo, you’ll need to take a bus or train from the aiport, and the driving time by bus is about 70 minutes!
However, that’s not always the case. In Pescara, Italy for example you’ll pay less than two Euro for a bus ticket, and reach the city centre within 15 minutes. The same goes for Riga, Latvia where you only pay like 1.50 Euro for the bus, and Montpellier, France as well as other places. Consider all this when booking a flight! Look up the airports, and the transportation fees, which are quite expensive in e.g. London and Oslo.