Question: Low cost airline SmartWings, and its parent airline Travel Service, are based at Václav Havel Airport 12km west of which European capital?
Context: Czech Airlines a.s. (abbreviation: ČSA, ) is the national airline of the Czech Republic.  Its head office is on the grounds of 6th district Prague, Vokovice.  The airline's hub is at Václav Havel Airport Prague; however, it has other bases in the Czech city of Karlovy Vary and the Slovak cities of Bratislava and Košice.  Today, it operates scheduled, charter, and cargo flights. Travel Service Kft., trading as Travel Service, is an airline based in Budapest, Hungary, operating charter flights out of Budapest Ferihegy International Airport.  It was founded in 2001 and is a sister airline of Travel Service from the Czech Republic. Come Fly with Me is a British mockumentary television comedy series created by and starring Matt Lucas and David Walliams.  Narrated by Lindsay Duncan, the series launched on 25 December 2010 on BBC One and BBC One HD.  A spoof of British documentaries "Airport" and "Airline", the series follows the activity at a fictional airport and three fictional airlines: FlyLo (a low cost airline), Our Lady Air (an Irish low cost airline) and Great British Air (a major international British airline). Travel Service Polska Sp.  z o.o. is a Polish charter airline based in Warsaw, Poland.  The airline commenced operations in May 2012 from Warsaw Chopin Airport.  Travel Service Poland is a sister airline of Travel Service. SmartWings is a low-cost virtual brand of the Czech airline Travel Service.  Travel Service operates scheduled flights to several European metropolitan and leisure destinations under the brand from its base at Václav Havel Airport Prague. VivaColombia is a Colombian low-cost airline based in Medellín, Colombia.  VivaColombia is the first true low cost carrier in Colombia.  It is partly owned by the founders of Europe's biggest low cost airline, Ryanair. Travel Service, a.s. is a Czech charter airline and the biggest airline in the Czech Republic with its head office on the property of Václav Havel Airport Prague in Ruzyně, 6th district, Prague.  It operates charter flights mainly to leisure destinations and also wet and dry leases aircraft to other airlines.  It has subsidiaries in Poland, Hungary and Slovakia and also operates scheduled flights under the brand SmartWings. Václav Havel Airport Prague (Czech: "Letiště Václava Havla Praha" ), formerly "Prague Ruzyně International Airport" (Czech: "Mezinárodní letiště Praha-Ruzyně" , ] ), (IATA: PRG, ICAO: LKPR) , is the international airport of Prague, the capital of the Czech Republic.  It is located 12 km west of the centre of Prague and 12 km southeast of the city Kladno.  It is, with over 13 million passengers in 2016, the busiest airport in the newer EU member states.  It serves as a hub for Czech Airlines as well as a base for Travel Service including its subsidiary brand SmartWings, and is also a base for low-cost carriers Wizz Air and Ryanair.  The airport is able to handle wide-body aircraft including the Airbus A380 or Boeing 747. Přední Kopanina is a suburb of Prague, Czech Republic.  It is located 10 km northwest of the city centre in the vicinity of Václav Havel Airport Prague and has a population of 667 (2006).  First mentioned in 1285, it was incorporated as a municipal district of Prague in 1974.  The main local sight is a Romanesque rotunda of St Mary Magdalene from the first half of the 12th century. Travel Service Slovakia is a Slovak charter airline based in Bratislava, Slovakia.  The company was founded in 2010 and operates from Bratislava Airport.  Travel Service Slovakia is a sister airline of Travel Service from the Czech Republic.
Answer: Prague