Swimming in Alpe d'Huez
There are a number of pools in Alpe d'Huez - the indoor pool at the Palais des Sports et des Congrès is open every day from 10am to 8:30pm (except during swimming classes) and entry is free with a Visalp pass.
The outdoor pool on Avenue des Jeux is also free with your Visalp pass (€3 without) and is open from 10am to 8pm. An outdoor pool may not sound that tempting in the depths of winter but this is kept so toasty that it often has steam rising from it! There is also a sauna and jacuzzi (€2.50 for 30 minutes) for relaxing those achy legs. Swimming costumes must be worn in all areas of the pool and chaps of all ages have to wear Speedo-style trunks which, rather disturbingly, can also be rented!
If you are happy to brave the cold you can take a dip (unsupervised) in Lac Besson. You can also fish at the lake and there is a nearby mountain restaurant with a sunny terrace and deckchairs.
Some hotels in town also have private pool / spa facilities - if you are looking for somethng a bit more exclusive it may be worth enquiring as to whether they are also available to non-residents, click here for details.