Köln is well-connected to the rest of Europe. High-speed trains connect Köln Hauptbahnhof station with Brussels, Paris, Düsseldorf, Frankfürt, Amsterdam, etc. London is only 4 hours by train with a transfer in Brussels (with Eurostar + Thalys, with Eurostar + ICE). Travel green and book your train on using the links (click here for other cities).
Long-distance busses call at the Central Station in Cologne (ZOB), the Köln-Bonn airport, and other stops around the city centre. You can explore bus schedules and book your trip on https://www.busliniensuche.de.
The closest airport is Köln-Bonn airport, but also the airports of Düsseldorf and Frankfürt are closeby. See this page for information on getting from the airports to the venue.
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