UEFA has fined Cologne and ordered them to pay Arsenal for damage caused by fans before last month's Europa League game at the Emirates.
The match, on Sept. 14, had to be delayed by an hour as thousands of Cologne supporters amassed outside the stadium, preventing home supporters from getting to the turnstiles.
Around 15,000 Cologne fans got into the stadium, the majority of them with tickets allocated for Arsenal supporters.
UEFA opened disciplinary proceedings after the incidents, and Cologne were hit with charges including crowd disturbances, acts of damage and setting off fireworks.
European football's governing body said on Monday that Cologne would be fined €60,000 and must reimburse Arsenal for the damage caused.
The Bundesliga club's supporters were also given a two-match travel ban, suspended for two years.
Arsenal had faced one charge over a blocked stairway in the away supporters' section, but UEFA decided not to open disciplinary proceedings against them.