The Francisco Sa Carneiro Airport, or Porto Airport for us laypeople is located 11 kilometres to the north west from the centre of Porto. The airport is the second busiest in Portugal both in regards to passenger number and aircraft movements, and has an IATA reference of OPO.
The airport was named at the time to honour the Prime Minister of the day, Francisco de Sa Carneiro, who was unfortunately killed in and plane crash on his way to this very airport. Prior to this the airport went by the name of Pedras Rubras Airport. The airport is a major facility for both Ryanair and TAP Portugal.
The metropolitan train service or Porto Metro provides transit to the airport via Line E. The metropolitan bus service or STCP can also be used to get to the airport from the centre of Porto which also runs at night. Alternatively you can catch a taxi or pre-booked transfer shuttle.