Hi, I am going to be staying in Madrid for 10 days in March. I was wondering if anyone had any opinions as to what accomodations are worthwhile. A 3 to a 5 star hotel would be fine, and of course something located in the center of Madrid. Near Opera or Puerto del sol would be a bonus!

I have stayed at the Westin Palace and it is very nice. It is near the Atocha Train station and across the boulevard from the Prado. I have also stayed at the Ritz, also near the Westin, but it is a bit run down.

I've got the perfect hotel for you, it meets all your criteria -- the Intur Palacio San Martin. This is one of my favorite hotels in Europe. It's a very nice 4* hotel and just a few blocks east of the Opera (and a couple north of Plaza Mayor).

Another good choice not far from Atocha Station is the Hotel Urban -- very modern and chic, full of chrome, leather and ancient primitive statues (a really interesting combination). At first I didn't care for the decor, but it really grew on me as I stayed there.

Hi-
I was in Madrid last month and stayed at both the Intur Palacio and the Westin Palace.
The Intur Palacio is certainly centrally located, a few blocks from Sol and easy to walk just about anywhere. The rooms are nice with good bathrooms. Exterior rooms seem a bit nicer than interior ones.
The Palace was absolutely lovely, very spacious room with fantastic beds and great bathroom. I found a good rate for the Palace on Priceline (about $135 plus tax), but there's no guarentee you'll get that hotel or rate.

I liked the Best Western Carlos V. It's close to almost everything (a very short walk to Plaza Mayor & puerto del sol).

See if Sol Melia has any special offers:
http://www.solmelia.com

We stayed at the Tryp Cibeles (Tryp is a chain under Sol Melia) and liked it very much.

We enjoyed staying at Hotel Mario (great location at Campomanes 4, a narrow side street off the Opera house plaza). It is small, newly renamed and redecorated -- sleek modern design, a good breakfast buffet, hip and helpful young English-speaking staff. About 110E for a double last April. Warning: some (but not all) of their double rooms are tiny.

I've stayed twice at The Villa Real which is almost across the street from the Palace . Nice rooms and bathrooms , although they are not huge they're more than adequate in size.
I stayed there in June/July and paid 140 Euros. Probably in March it would be less than that.

see www.bancotel.com
www.gtahotels.com for some price orientation.

you might find a mentioned hotel at a discount.