It has to be Gatwick! Both runways can't be operated simultaneously, there are two terminals (North and South), BA has a large hub here, although as BA centres in more and more on LHR for Long-haul, etc, LGW could lose more of the spotlight. More flights to the US depart from LGW, then any other European airport, and there is about 31 million expected to pass through LGW this year.
London Gatwick International Airport is my...(dare I say) Final Answer.
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