Situated in heart of Madrid, where Atocha street meets the Plaza de Jacinto Benavente - at beginning of what all the guide books proudly call the "Ruta de los literatos" (men of letters way), we find one of the most emblematic buildings of the cultural life of Madrid:
The Calderon Theatre of Madrid.
It is of the constructions most admired by all the walkers of Madrid, which front has presented to the biggest artists of our country, reaching to all the kinds, from the magazine to musical, for the ballet or the comedy. Source: http://www.teatro-operacalderon.com/
I didn't get in here but took a picture of the great architecture. If your into the opera you can check out their web site. It is in a great location in the heart of Madrid.
The Royal Theater was closed from 1988 until 1997 due to structural problems. However, the new version has been completely modernized while retaining the charm of the original structure (classic opera house balconies, plush seating, etc.).
Dress Code: Dress well. No jeans or sneakers.