Birmingham (BHX) is a medium-sized city located in the West Midlands county of the UK. The airport has a railway station (Birmingham International) that is managed by the Virgin Trains West Coast franchise. Birmingham has a tour rating in the early 100s and a business of ~200 when the game first starts. These ratings can go over 300 with business usually being higher than the tourist rating.
Birmingham International Airport (BHX) is the default airport.
Birmingham's location in the middle of the British Isles make it a good place to make your hub. It is roughly 5000km away from the eastern coast of the United States and is close the the European mainland. Not many people choose Birmingham as a hub due to the fact it is overshadowed by bigger cities such as Glasgow,London and Dublin. The city can sustain light to medium competition and monopoly routes are common from Birmingham.
The default airport will be enough to handle the traffic of the city and the airport will only reach higher levels towards the end of the game. Buying the national airport could be profitable but it is advised to not buy it as the 60 credits could be better spent elsewhere.
Planes with medium capacity such as the A320/B737 family are good for continental European routes, even E-Jets or CRJs for some small cities such as Reykjavik. B757s and B787s are recommended for routes to the Americas and beyond as Birmingham would not be able to match demand for an airplane such as the A340, and would dig into your profits.