Not for light sleepers!
First of all, our stay was great in general. The apartment is perfectly located a few steps away from the cathedral. In Porto, you can pretty much walk everywhere and we loved the location of the apartment. That being said, you will have to put up with a lot of noise! Especially from inside the building. It is true we travelled in the heart of the summer, and maybe off season is more quiet, but we could pretty much hear everything the neighbours said. And anybody coming up or down the stairs would wake us up. If you are not a light sleeper, this apartment is just perfect! Clean, beautiful, well located. We were nicely welcomed and were given amazing tips and recommendations. The noise was just too much for us.