The European gas market is a huge network of producers, consumers, and various forms of gas processing and storage. To understand this market fully, all of these factors have to be explored and explained. When the gas market is described as a network flow problem a multitude of factors - including data quality, poorly defined limitations, decisions only known to the individual actors in the market, and solution speed - put a limit on how accurate this description can be. This thesis shows that based on public and semi-public data the entire northern European gas network can be modelled as a general network flow problem and solved by a mixed-integer-problem solver. This model is then shown to be easily converted into a fully linear program, which can be solved in significantly less time with almost no loss in precision.