Frankfurt, Germany - Frankfurt Intl (FRA)

In Brief: Germany's busiest airport, Frankfurt International ranks third within Europe in terms of passenger traffic. Unlike some other of Europe's bigger airports, there is not a separate terminal for low-cost airlines. There are, in fact, not a huge number of budget airlines offering flights in and out of Frankfurt, but those that do are distributed across terminals. Air Berlin, Clickair, and Niki fly to Frankfurt International. Transportation: The best way between the airport and the Frankfurt main train station is by S-Bahn. A one-way journey costs just €3.55 and takes about 10 minutes.