Our friends over at Photokina has an excellent website on everything you need to know in regards to travel, hotels, arrival from airport and transportation.
Information below is taken from the Congress Center Easts website.
BY CAR
please follow the green Koelnmesse signposts. These will guide you in the area around the exhibition centre directly to car parks provided close to the Congress Centre East.
Please note: since the 01.01.2008, the Cologne city centre is an environmental zone, which only vehicles in the pollutant groups 2 to 4, and which bear the corresponding plate are allowed to enter. You will find further information at Umweltzone.
BY RAIL
if arriving at Köln Messe/Deutz you can reach the Congress Centre East on foot (approx. 350 m) by following the signposts.
if arriving at Cologne Central Station, take the S6 (in the direction of Essen), the S13 (in the direction of Troisdorf), the S11 (in the direction of Bergisch Gladbach), the Regionalexpress RE (in the direction of Koblenz or Köln Messe/Deutz or Hamm (Westf.)) or the Regionalbahn RB (in the direction of Oberbarmen or Overath), which will take you to Bahnhof Köln Messe/Deutz. On arrival at the Deutz Bahnhof station you can reach the Congress Centre East on foot (approx. 1,000 m) by following the signposts.
BY TRAM
take tram No. 1 (in the direction of Bensberg) or 9 (in the direction of Königsforst) which will take you to Bahnhof Köln-Deutz, or tram No. 3 (in the direction of Thielenbruch) and 4 (in the direction of Schlebusch) which will take you to the “Koelnmesse” stop immediately in front of the Congress Centre East.
FROM COLOGNE/BONN AIRPORT
take the S-Bahn No. 13 from Cologne/Bonn Airport to the “Deutz/Messe” stop (journey time approx. 15 minutes); from there the footpath to the Congress Centre East is signposted.