Possible test sites in Germany can be found using the following link:
Important notice: To access the trade fair grounds, you will need an official EU Digital Covid Certificate (EU DCC) as proof of your negative test result. Please filter for "Digital Covid Certificate" in the overview for this purpose. No other test procedures are permitted. For non-EU citizens without access to the EU DCC certificate, the following exception applies: Click here for all information.
For test centres near the Cologne trade fair grounds, you can enter the postcode 50679 in your search.
At Koelnmesse trade fairs in 2021, it will be possible to take a Covid test on the premises of the respective event for a fee. More information: Will testing be offered on the trade fair grounds or prior to entry? And/or at Cologne Bonn Airport or Cologne Central Station?