It is very convenient as everything is in within walking distance.
1) The things we didn’t like about this place is that on Expedia, it said they had air conditioning but turned out they really didn’t. So, the room was very hot even with the windows open and we couldn’t sleep, so checked out after the first night to go stay at a different hotel.
2) The staff must use vinegar to clean, so the smell of it just linger so strongly in the hallway and it was just horrible. Also, the repair crew kept things lying around in front of the doors, so it was very inconvenient for us to exit.
It was not a good experience for us as we couldn’t sleep at all, but if you are okay with not having an AC, then it is definitely in the Köln’s prime spot.