Stayed for one night in March. The hotel is a big concrete block but centrally located for the old part of the very picturesque town of Pamplona.
The rooms are functional and clean but the soundproofing is terrible. I could hear the people in the next room talking and it wasn't even muffled.
There is a small pool in the small garden area, but as it was March it wasn't warm enough to use it.
The whole hotel comes from the 1970's in decor and I am surprised no-one has bought this hotel and refurbished it to a high standard, there must be demand for a 5 star hotel in Pamplona.
Didn't eat in the hotel but went to a fantastic restaurant opposite the bull ring called Hartza. Run by two sisters, they do not speak very much English but appreciated my attempts to speak Spanish and I ended up writing out the order for my table of six for them. Very friendly and very reasonably priced.
Pamplona is an ideal place for a romantic break but I just wish the standard of hotels were better.

There is nowhere in town to stay during the San Fermin festival, including Hotel Tres Reyes, where you will be able to fall asleep at night. The noise is incredible. Unless you enjoy drinking all night, and sleeping (after the "encierro") between 8:30 a.m. and 4 p.m., or you are deaf, you will not sleep during the night. The 2005 outside amplified music stage was the largest and loudest portable system I have ever seen in my life. The screen at city center came in on a semi-trailer and "unfolded" to about forty feet high. The speakers would not fit in most gymnasiums. If you want to sleep, stay outside of the old portion of town.

Hotel Tres Reyes is supposed to be the nicest in town, but there is no soundproofing of the exterior walls or windows. Actually, the exterior walls that contain the windows are some type of flimsy metal that move when you push on them. It felt and sounded as though, even with custom-molded earplugs, that the bands were right outside my window, with music pounding non-stop at unbelievable decibels until 6:30 am. For the noise factor, I will not stay at Hotel Tres Reyes again.

Otherwise, Hotel Tres Reyes is good because it is centrally located (in the old portion of the city where everything is happening), has a good breakfast buffet (that is included with your stay), representative of the local Navarra breakfast foods, and has a professional staff. It was the most expensive Pamplona hotel I found when searching in 2005, so I figured it would be a good choice. The hotel agressively rates itself as a four-star hotel, but I would properly classify it as a three-star. Note that the included photos shown are not of Hotel Tres Reyes, as the hotel is not on the route of the encierro (bullrun). One must rent a balcony for such observation, done by contacting a local agency that rents them from owners.

The problem with staying outside the city center is that you will walk for a half hour to get anywhere, you will be far from anything happening, and you will most likely not get a taxi, since thousands of others are competing with you to get one. Forget driving, because the city center is impossible to negotiate during the festival unless you are on a motorbike. The real problem is finding a parking spot once you get to the city center, as they are quite coveted.

In sum: San Fermin festival is a giagantic booze-fest that the world descends upon for eight days, not to be missed. If you don't want to sleep, stay in city center, and Hotel Tres Reyes will suit your needs. If you need to sleep when the sun goes down, stay outside the city center and bring some walking shoes. Book one year ahead.

I was in a party at the Hotel to attend a family wedding nearby in September 2004. We all found that the Tres Reyes gave us good courteous service. The whole place must have been refurbished recently for everything was in good condition and all equipment worked. The location is central and convenient for the visitor who wants to explore the old town on foot. The hotel is quiet and has adequate parking.
The food is unremarkable but the servings of spirits in the bar are generous.