There was just one problem - they had chosen the wrong hotel.
To emphasise their ambition to disturb the travelling players' sleep, ahead of their Champions League clash, the Turkish supporters posted a video on social media platform 'X' (formerly Twitter) with the message: "Welcome to Hell, FC Copenhagen".
But Daniel Rommedahl, director of football operations and international affairs for Copenhagen, said in a comment on the incident that these Galatasaray's fans had turned up at the wrong hotel.
Rommedahl has further commented on the incident to Bold.dk: "We haven't heard anything, and when I look at the video, I can clearly see that it's definitely not (where we're staying)."
"It is 100 per cent certain that it is not near. It's also not our sponsor hotel or the hotel for the under-19 team, so whoever is staying there... God knows," he added.
Copenhagen will face Galatasaray on Wednesday evening at 18:45 CET in Istanbul.