Brussels Airport is located in Zaventem, 11km north of the city. It is connected by rail not only to Brussels itself, but to other Belgian cities like Antwerp and Bruges and other European cities, including Rotterdam (1h45m), The Hague (2h05m) and Amsterdam (2h55m) in the Netherlands.
Brussels has two main rail stations: Midi/Zuid (South) and Nord/Noord (North) but they are on the same line that crosses the city from North to South. There are other secondary stations along the line, such as Central/Centraal, Congres and Chapelle/Kapellekerk. From the main North and South stations there are trains to many European destinations, including Paris, Lille, Frankfurt, Cologne, Amsterdam, The Hague and many others.
Eurostar trains to Brussels South (Midi/Zuid) from London reach the Belgian capital in about 2 hours.