Within walking distance to all the attractions. The hotel staff spoke excellent English, and were very helpful. Very clean rooms, with nice bathrooms. Quiet as well. PC available for use.

It’s a hostel, but it can be treated as something much better. They have several buidings, and we were moved to another one (comapratively to the address of the hostel). The room was wonderful: creative interior, good furniture and bathroom. We felt like at the appartment, not in a room of a hotel!
Location was very convinient, not far from the metro station and Prado museum. Quality-price ratio was very good. They had the PC for the joint use, but we did not try it.
With pleasure will come back there again.

I selected this hostel because it was one of the cheapest I could find that still had a great location. Note: Hostel Martin and Hostel Cervelo are the same hotel, just on different floors of the same building. Not sure why they have different names. We stayed on the Cervelo floor. When we checked in, the receptionist asked us if we would be willing to stay at another hotel of theirs a block away that had also been recently renovated. We said no and she did not press the issue.
The location cannot be beat. We hardly even had to use the Metro because it was so easy to walk to most places we wanted to go.
The room appeared to be recently renovated and was cleaned daily. Our bed was comfortable and the wi-fi worked in our room perfectly. The room itself and adjoining bathroom were both small, but this was only an issue when both myself and my boyfriend were trying to get ready at the same time.
We requested an exterior room so that we could have a window. There was quite a bit of street noise, garbage pickup every morning, car horns, etc, but for us this was not a concern. The interior walls are quite thin. I could hear the noises from the neighboring room and hallway quite well. It was annoying, but not ridiculous. If you are a light sleeper, I would bring earplugs or stay somewhere else.
The staff was accommodating to us. A few of the staff were very friendly/nice and others not so much.
You cannot print directly from the lobby computer. We needed our boarding passes printed for a flight and we had to e-mail them a pdf and received the print out a day later. Not that big a deal, but annoying that we had to wait and it was more of an ordeal than it should have been. We were unable to purchase train tickets online because we couldn't print them immediately.
Over all I would recommend. There are some things lacking, but for the price, I feel it is a good value.

OK place to stay, pretty good location, not much in terms of amenities. If you need a reasonbley priced place to stay that won't break the bank this is fine.