This apartment is very close by to the main city centre and also to quite a few subway stations. All the typical city attractions were easy to walk to. The apartment is on a pretty quiet side street just off of Calle Atocha so I did not hear very much street noise.
Santiago is a very gracious host. He gave me very detailed directions from the airport and met me at check-in. The apartment was spotless and well-appointed. The WiFi worked great.