First time in Madrid. I'll make a 6 hours stop in betwen planes. Is it enough to hop on a bus or train from the airport to center of town, take some pictures and come back for my next flight? What's the best way to do this? Thanks to anybody that can shed a light into this.
Alex

Six hours should give you plenty of time to hop on the Metro and spend a few hours in Madrid before your next flight. Just be sure to allow enough time to go back through security.

You should take metro form Barajas airport to Nuevos Ministerios stop (Line 8, pink, travel will take 15 minutes). This metro station is in the middle of Paseo de la Castellana, the main street of the city, you can take bus 27 to Cibeles circus (it will take another 15 minutes), where you can see Banco de España, Puerta de Alcalá, Correos headquarters, Prado Museum and walk to Sol too. Ejoy it

Just watch your pockets while you are on bus 27, it is notorious for its crafty pickpocketers (so I have been told).

I ride bus 27 frequently (at least 1-2x per week) and have never had a problem, but have been warned... by Spanish citizens. So, just passing along the info.

Have fun!

It depends on how late your flight from Chicago is delayed I haven't had too much luck with flights in the US the last couple of times so that 6 hours may turn out to be less. Also it depends on where the next flight takes you.

Otherwise yes, you should be able to get out again depending on the day and time. If you hit rush hour, the metro would be the best choice. If not then a taxi might be the quickest use of your time. They are not too costly from the airport to the major areas.