Deafening noise all night long, and I am not referring to the hubbub of people in the square below the house or the street performers' concerts, but to the 24-hour construction site under the balcony. We had booked for one night after a long car trip, wanted to enjoy an evening in Porto, and we did until we arrived at the apartment. The location would be nice but certainly not at this time (and this time I found out will last for two years or so) because right under the balcony is the 24-hour metro construction site with deafening noise that didn't allow us to sleep through the night. The hosts left earplugs for us on the nightstand, but the noise is so loud that they are practically useless