I quite like to go often to Spas and have a break out of the stressy life, and noisy city.
Now, I found an urban one, very central, absolutely as!.

Based on Calle Barquillo 43, near Chueca tube station, that gorgeous spa called "Spa Relajarse" is just nothing like as I saw before.
Minimal zen decoration, exudes posh and profesionalism, twilight zones, absolutely silence, (very hard to found in any part of the cinty center). and two spotting cleaning floor.
Basicly from 55€ you rent the spa for your own,and, even if you're not alone in the premises, you'll never see or listen to any other costumer, giving this fab idea a luxury, exclusive touch, (and they have a big range of treatment: from mug applications, peeling, massages, oxigenteraphy, termal facilities, turkish bath, to a huge climated pool with jacuzzi area).
All this for you. You can stay 1,30mt / 2h depend of the treatment you had booked, (It always has to be booked in advance).
I highly recommended this place, so if you're living here or planning visit Madrid, and you want to treat yourself with a luxury posh and relaxing afternoon, don't think twice, and go for that one!.

Spa Relajarse.
C/ Barquillo 43
tel : (0034) 913086148.
Open daily from 11 am till 23pm.
http://www.sparelajarse.com/