Which European city is served by airports with International Air Transport Association codes ARN and BMA?

The International Air Transport Association (IATA) publishes codes that are abbreviations to facilitate air travel. These IATA codes uniquely identify locations, equipment, companies, and times to standardise international flight operations.

Many IATA airport codes just use the first three letters of the city in which it is located, for instance: BER (Berlin), EDI (Edinburgh), GLA (Glasgow). Three of the answer options follow this simple pattern: Aarhus (AAR), Amsterdam (AMS) and Bremen (BRE).

Stockholm is different. Arlanda Airport (pictured) is the city's main international airport, located some 37 km (23 miles) from the city centre. Arlanda’s IATA code is ARN, not ARL (which is assigned to an airport in Burkina Faso). Bromma Airport is older and just 7.4 km (4.6 miles) from the city centre it still has some scheduled flights the domain of business jets, general aviation and flight schools. Bromma’s IATA code is BMA, not BRO (which is assigned to an airport in Texas, USA).

There are two other airports that serve Stockholm but are very remote from the city: Skavsta (code NYO) is about 100 km (62 miles) away and Västerås (code VST) is about 110 km (70 miles) away; these have catered for low-cost airlines and other general-aviation traffic.