The Caixa Catalunya's Les Planes de Son centre is situated in fields close to the town of Son (Pallars Sobirà), which Caixa Catalunya acquired in 1998.
Son, at an altitude of 1,393 m, is one of the highest-situated in the Àneu valleys. It lies 7 km from Esterri d’Àneu and, at present, has 25 inhabitants as a result of a decline in its population which began in 1860.

Its mildly stepped appearance is characterised by the outline of the Romanesque Sant Just i Sant Pastor church, which exemplifies the traditional architecture of the towns in the mountains, in spite of the changes that the new use of the land is causing.

Son is in one of the best-preserved regions of the Pyrenees, the Àneu valleys. Located right in the middle of the Pyrenees, the Valleys are a sub-county covering a little more than 407 km2 and occupy the upper part of the county of El Pallars Sobirà, in the north of Lleida province.

The Àneu valleys consist of 6 main valleys and many more secondary ones:

• The main central valley, running from north to south, contains the villages of Escaló, La Guingueta d'Àneu, Escalarre, Esterri d'Àneu and València d'Àneu.
• The other side valleys are as follows: in the north, the Isil i Alòs valley; to the west of the central valley and running from north to south, the Bonaigua and Espot valleys; and to the east of the central valley and running from north to south, the Unarre valley and Berrós coomb.