Critical to protecting the port of Liverpool and the industrial North West, as well as discouraging attack via Ireland, airfields were quickly established in North Wales after the outbreak of war in 1939. This book assesses the role of the twelve bases in the area from fighter stations such as Valley and Mona on Anglesey to training and support centres such as Penrhos, Wrexham and Hawarden, the airfield associated with the factory producing Wellington bombers.