From International Adolfo Suarez Madrid Barajas Airport, take a taxi or use line eight on the underground to get to the city center. You can also take the train (line C1) from Terminal 4 to the city center. 

Bus services are also available. You can take the express Line 203 from Terminals 1, 2 and 4 to Atocha Train and Underground Station (every 15-20 minutes from 06:00 to 23:00 and every 35 minutes from 23:00 to 06:00). The night bus is called N27 Airport Express.