It might be a little small for three, but my wife, and then twelve year-old son and I lived at this wonderful apartment for three months in 2002. The location could not be better. It is at the intersection of Calle Huertas and Calle Jesus.

Within walking distance of Sol, the Prado etc., in an area full of bars and restaurants, a great bakery, and the Bar Roda. The latter being the home of the greatest napolitanas de crema in the world.

http://www.inicia.es/de/elprado/