Cologne has a very good subway/tram and bus network "KVB" Kölner Verkehrsbetriebe; one- and three-day-passes are available. The tickets are valid for subway, tram and regional train within the VRS-network. Trips within the city limits require zone 1b tickets. For short trips of up to 4 stops on subway, tram or bus there is also the slightly cheaper "Kurzstrecke" short trip ticket. A map of the network should be found at any station, and official Kölner Verkehrsbetriebe cologne station maps are available online here (http://www.kvb-koeln.de/s...).
Cologne's subway and tram-system, or U-Bahn, is a mixture between both systems: A subway line can go on street-level and end up as a tram or vice versa. There are vending machines or ticket-offices at larger stations The trains and buses also have vending-machines. See the public bus, tram and subway-company KVB (http://www.kvb-koeln.de/g...) for printable maps of the bus/tram/subway system and (http://www.kvb-koeln.de/s...) for their official street map (http://www.cologne-in.de/...) of Cologne.
Regional Trains are known as "S-Bahn", "Regional-Bahn" and "Regional Express". Most of them don't have ticket vending-machines so remember to buy a ticket at the station.
Cologne has, like Berlin, Munich and Frankfurt, a Call A Bike - System. After you register for an account online, it will charge your credit-card a per minute fee. You can pick up or drop off one of the silver-red bikes anywhere in the city. See here (http://www.callabike.de/-...) for details. It is also possible to rent a bike at many different places, by bike is maybe the best way to go around in the city.
But, on the whole, the centre of Cologne is not that big for a city of one million. It is entirely feasible to walk from one end of the centre, say, the Rudolfplatz, to the other end, say, the Dom, on foot in half an hour.
Student Travel Tip: Student travel til 20 years can be very cheap to and from Cologne, as well as the state North Rhine-Westphalia. The German rail company DB: Deutsche Bahn offer a 'SchöneFerienTicket NRW' during student holiday times and allows free travel throughout Northrhein Westphalia on local buses, trams, U-Bahn, S-Bahn and Regional-Trains. Prices range from around ⬠54 for summer holidays to ⬠25.50 for Easter holidays, but prices and tinmes change year-on-year.
The ticket is available to anyone with valid student identification student union card, enrolement card etc. and personal identification passport, driving licence etc.. Note: the ticket is only valid for student holiday dates of Northrhein Westphalia and the ticket is not valid for high speed express trains. Visit/contact Deutsche Bahn (http://www.bahn.de/region...) for more information before travelling to Germany.
