It is very easy to get from the airport into town, just take the bus 12 which calls right outside the offices of the car rental companies opposite to the terminal building. The journey will take ~30 minutes to the railway station, (Gare SNCF) or ~20 minutes to the city centre. A one way ticket costed 0,90 Euro in December 2009. There is also a shuttle bus, but the ticket, which is valid for 48 hours, costs 4 Euros (Dec. 2009).
Paris’ 'third airport' is located about 55 miles north of the French capital. Beauvais Airport (airport code BVA) is home to many low cost budget airlines: Ryanair, Wizzair, Sterling, BlueAir and Norwegian Air Shuttle.
There is direct bus service to and from Paris leaving from Porte Maillot. Busses leave 3 hours before and 20 minutes after each flight and take about an hour and twenty minutes.
At Beauvais is the airport used by Ryanair and other low fare companies to/from Girona/Barcelona and Milan and other cities.
From Paris to Beauvais airport (BVA), take a bus at Porte Maillot station, Metro Line 1; the bus stops in a parking, outside the station with any indication. You must ask directions.
The trip last 1h 10m and costs 13 euros.