The flat is very cozy and extremely well located. We spent four days in Madrid and did not need to use any transport system, because most attractions like Prado, Reina Sofia, Retiro and Palacio Real are within walkable distance; Callao metro station is just a few steps from the doorway though. Despite being close to many cool restaurants and bars, we were not bothered by any street noise in the apartament. I would definitely book it again in my next stay in Madrid.