The hotel was extremely noisy throughout the night. This continued for 3 nights in a row. One side of the hotel is facing an ally, where people are talking, working and moving stuff all night. It was just terrible. Normally i'm not a good sleeper, so blame it on myself. This time, colleagues were in other rooms and didn't sleep either.
At checkout I told the staff and there response was one like "1st time we ever heard it". The same staff, other people complained to in the morning. Apparently, they are trained to ignore.