Booked a windowless room by mistake (my fault) and only realised once I entered the room. Ran to lobby to see if i could change to a room with a window but they had no availability for the night I was there, and I had already paid so I had to stay. The windowless rooms are extremely claustrophobic, would definitely not recommend. Thankfully I was only there for 1 night, I couldn't wait to leave. Tried to stay outdoors as long as possible. Not even sure how this is legal or safe in terms of fire safety. The windowless room I had was 2 floors below ground, essentially in the basement. It didn't feel super hot but you definitely feel like you're in some kind of box. The room is pretty small but fine for 1 person. Other than that the hotel is fine & the room would have been totally fine if it had a window. The price is still way too high for a windowless room but location is amazing (a few minutes walk from everything, including the airport train). Check in was fast. Breakfast buffet was totally fine and had varied options. The bathroom has glass walls, not an issue for solo travellers but it would be awkward for groups of 2. Bathroom needed more deep cleaning. Walls are thin, I could hear people coughing in the room next to me, and other noises in the hallway, this is quite bothersome. Room has most amenities except mini bar. Would absolutely not recommend a windowless room for stays longer than 1 night. Beware since it isn't unusual for hotels in Stockholm. Fast check out!