Stayed for a few days at the end of May as part of a Brittany Ferries holiday. I have always found the hotels chosen by Brittany Ferries and the value that the company offers as excellent and because of this have travelled on numerous occasions with them and the car throughout Spain. My main problem that I had with the Corona de Castilla was that at the end of May the weather was up in the mid 30's.
No problem except that they would not switch on the air conditioning before 1st June. This made our room which was at the front of the hotel and covered by afternoon and evening sun unbelieveably hot. Using the room thermostat as a guide it was 36 degrees but the management would not budge. We resorted to using wed bed sheets for cooling in an attempt to get some sleep. We were given a large fan but the noise from this brought its own problems. Besides this the hotel was nice and typical of a 4 star spanish city centre hotel. The only other problem was parking. I did not pre-arrange this in their small underground car park which was a mistake.
I think that there are two things to consider if thinking about staying at this hotel, if you take a car arrange parking and if the weather there before June 1st is hot then please don't bother as you will really suffer.

Everything worked in the room, FREE WIFI And ROOM SAFE added to the pleasure. Comfortable bed in quiet room. You'd need to be pretty fussy to not like this hotel. Easy walk up to the cathedral

Great location just steps from the old town and the cathedral. Convenient inexpensive parking at the hotel. The rooms were clean and the bed comfortable. The step down from the bathroom was a little trciky, though. I found th hotel a great place to stay and a good value for visiting Burgos.