Cologne police reported taking their first drunk man into custody just before 11am Thursday.
As the day progressed – and the Kölsch continued to flow – more people were taken into custody while others were encouraged to go home.
Police were also called to Cologne's central train station when an abandoned suitcase was found. The area was cleared and the case opened to find only personal items inside. The owner has yet to turn up.
Broadcaster WDR reported that police had around 60 calls to attend to at 2:30 am on Friday, including several fights. One police officer was slightly injured.
First responders also answered 202 mostly alcohol-related calls. Ambulances said severl people had to be brought to hospital for overindulgence, but only eight of those were minors.
In neighbouring Aachen, four police officers were injured in breaking up fights around the city.
Despite the number of brawls, fights and fights, all Rhineland police called it a peaceful evening, "comparable to those of previous years".
Karneval is known as the "Fifth Season" and starts in November, culminating in a five-day party to mark the end of the season on Ash Wednesday, with the idea being that revellers get all their indulgences out before Lent.