Cologne/Bonn Airport(IATA: CGN) is located in the district of Porz in the city of Cologne, Germany, and is surrounded by the Wahner Heide nature reserve.
It is centrally located in the Cologne/Bonn Region 14.8 km (9.2 mi) southeast of Cologne city centre and 16 km (9.9 mi) northeast of Bonn. Cologne Airport is the sixth largest airport in Germany and one of the country's few 24-hour airports. In terms of cargo flights it is second. In 2007 the number of passengers increased to 10.47 million, from 9.9 million in 2006.
Here are some of the major Airlines that service Cologne Airport:
Austrian Airlines operated by Tyrolean Airways
Bulgarian Air Charter
KLM operated by KLM Cityhopper
Lufthansa operated by bmi
Lufthansa Regional operated by Eurowings
The above mentioned information is taken from: http://en.wikipedia.org/wiki/Bonn_airport