The apartment is in the city centre which is absolutely amazing - you can get on foot to most of the places you'll want to visit. I previously spent 4 months in Porto studying and came back now for holiday and I feel like this is one of the best locations to choose for your staying. For example, in 10 minutes you can get to Ribeira, in 5 minutes you are at São Bento from where you can get a train and explore other cities and you have several metro stations around your house which enables you to get easily to all lines. You share the flat with other guests, but there are 2 bathrooms which I consider to be a great advantage. Fruit and vegetable lovers will appreciate fresh staff from the Bolhão market which is just accross the road. And the cats are very friendly :)