Flying is not the only option
In addition to allowing you to enjoy the scenery, trains are a good option for travelling around Europe, especially for short-distance destinations. If you are going to a more distant place you can also take a night train, combining sleeping and travelling in one.
InterRail: the pass to travel in Europe by train: if you plan on visiting several different countries, save some money by getting an InterRail pass. Just check the combinations that better suit your route around Europe and hop on and off many of Europe’s trains by simply showing your InterRail pass.
RailEurope: create your own train itinerary by searching among 50 different train companies around Europe.
Railfaneurope: a gateway to European national railways websites.
RegioJet: although less prominent than its bus equivalent, the train service of the same name can be used to reach a couple of major cities in Europe.
Travelling by bus shares some of the advantages of the train, such as the chance to enjoy the view and to travel during the night. Even though it can be slower at some points, it can be your only option to reach a remote location.
Eurolines: a long distance coach organisation, Eurolines connects all the major European cities. Discover different destinations and timetables.
Busabout: this bus service identifies itself as an alternative choice with a freestyle form of travel and unique hop-on hop-off flexible coach network.
Megabus: low cost option for intercity travel around Europe.
FlixBus: bus service with routes mainly in Western and Southern Europe but lately expanding to Central and Eastern Europe as well; be careful with routes connecting multiple cities as you can easily experience delays.
RegioJet: service operating bus routes mainly in Central Europe, especially Czech Republic and Slovakia, but you can reach major European cities with it as well.
Deutsche Bahn: the German railway company also operates couple of convenient and international bus routes.
Whether you have a car or not, you can still choose the car as your transport method around Europe. Carpooling is flexible and you don't event have to know how to drive. As a driver or a passenger, you share the expenses and meet new people along the way.
Carpooling.com: cheap and green way to travel throughout Europe, connecting people across 40 countries.
RoadSharing: car sharing and hitchhiking.
Blablacar: it connects drivers who have empty seats with people looking for a ride around Europe.
It may have never crossed your mind, but an overnight ferry can sometimes be your best option, especially if you are around the Mediterranean or Scandinavia.
Ferrylines.com: search among over 1.800 ferry routes in Europe.
Aferry.com: over 1200 ferry routes throughout the UK, France, Spain, Ireland, Holland, the Mediterranean and the rest of Europe.