Lille is a city located at the crossroads of Paris, Brussels and London. It may be reached by train or by plane.

By plane: from all around the world, Roissy-Charles De Gaule Airport is less than one hour far from Lille railway stations

http://www.aeroportsdeparis.fr/ADP/en-GB/Passagers/Home/
http://www.easycdg.com/pages/indexpag.html

Lille-Lesquin airport is also available for interior lines
http://www.lille.aeroport.fr/

By train: The two train stations in Lille are one hour far from Paris-Gare du Nord railway station by high speed train
http://www.voyages-sncf.com/

And from neighbouring European countries, Thalys and Eurostar high speed trains are available
http://thalys.voyages-sncf.com/
www.eurostar.com