I have a brief window in Madrid this Sunday, obviously not as long as I would like. I'm staying about 2km east of the Plaza de Toros. I don't have a car but I'm happy to hop on the Metro. Any suggestions? Thanks.
Jason - read this thread on exactly the same topic. Everything mentioned in the thread you'll read can be done by walking. http://www.ricksteves.com/graffiti/helpline/index.cfm/rurl/topic/56670/madrid-in-4-hours.html
Walk along the Gran Via and then down to the Prado...fantastic sites and parks along the way. The Park Retrio on a Sunday is outstanding. A brief (if that is possible) stop at The Prado. Or go from Puerta del Sol to Plaza Mayor and then on down to the Palace and the Cathederal Alumedena adjacent to it. Be sure to wear comfortable shoes and stop along the way.
If you are the least bit interested in art then I suggest using most of your time for the Prado. It is one of the best museums in Europe. Use the rest to just walk around the center and eat some nice food. Otherwise there is the palace and cathedral.
If you are there at the right time on Sunday and already close to the Plaza de Toros, you could always attend a bullfight. They are very exciting and should be seen at least once. They are a part of the Spanish culture. I don't know if the season has already ended? If you go, don't forget to rent a cushion inside, the seating is on concrete.