Our Diamond suite was an upgrade given to us at check in. We arrived on an early morning flight, but were allowed to check at 2pm. That was a big help,. since we traveled overnight. The room was nice. Bed was comfortable. It got a it warm at night, even though the only window was open, but only barely. The shower operation was confusing and not very easy to operate. The tub jacuzzi didn't work, or we could not figure out the operation. Restaurant was excellent as usual, plus it was expanded since our visit in 2017 and possibly due to Covid. Lobby bar also a new addition.

The hotel is very close from the airport and Blue Lagoon.
We got upgraded to Diamond Suite, it was amazing. Versace interior, luxury.
I asked for a taxi arrangement to Blue lagoon, the fare was discounted for Hotel Guests.
Very nice restaurant and bar.
Breakfast buffet was amazing.
If you come visit Bluelagoon, stay here Hotel Keflavík!

Rolled up in the taxi and thought it looked nice. No one there to help with luggage so we rolled it in ourselves. We were sent to the wrong room, and told it had no breakfast included despite having an email stating it had breakfast. It was the Diamond Suites and we were supposed to be in a nice room with use of the shuttle. No such thing was offered so we had to pre book a cab to get to the airport. Room was FAR TOO COMPLICATED. I couldn't figure out the tv despite the instruction manual ( I've never had an instruction manual for a hotel room before) so we gave up. The tub took 10 minutes of pushing buttons to figure out how to turn the water on and take a bath and not get hit in the head with water from the shower. We are both electrical engineers and pretty tech savvy but the hieroglyphics on the controls were impossible to understand. I did manage to get pretty lights on but I wanted a hot bath after a long vacation. Went to dinner and were pretty much ignored as we weren't icelandic people. Food was ok, waitress polite enough. Couldn't use half the USB chargers in the room because they would just charge, stop, and then charge again, over and over in a random cycle. Hung my breakfast placard on the door with our selections by 11pm (said to hang by 3am) but at 7am it was still there. Went down to have breakfast to get told again your room doesn't include breakfast but, yes, here's the email, AGAIN, that says it does. Oh, and partying people outside the room at night meant you had to leave the windows closed so we suffocated until 3am until we could open them to get some air. The light blocking shades (which required yet another remote control to use them) didn't block the Icelandic 24 hour light either. I had to use my eye mask. Apparently Thursday starts the weekend in iceland. Did I mention that even turning lights on in this 'modern' room was a struggle? A simple light switch would have been nice - technology is great, but I feel sorry for anyone who gets this room that isn't at least a bit tech savvy Oh, yeah, there is a bidet in there too - that was at least fairly straight forward. I can say it was clean, so that's why it gets the rating it does.