Fishing is popular in the Ariège. In season (mid-March – mid-September) you are likely to pass fishermen on the road up to Sentein hoping to hook a trout or two. Single day fishing permits (€12) are available from the local tabac in Castillon (11km), so remember to bring your rods.
There is a good tree free section of river bank a short walk down stream from Sentein. A hydro-electric damn at Bordes (9km & restaurant) is a popular spot with locals while in a side valley above Bordes, Lac de Bethmale (18km) is surely one of the prettiest lakes to fish on.
Although the river at Sentein is too small to navigate, by the time it reaches Engomer (16km) it has grown large enough for rafting to be exciting. Nunayak offer trips on the river from their Engomer base using either inflatable rafts or hybrid kayaks. All the gear necessary is included in the hire for a 6km trip lasting 1½ hours. The price per person is €25.
Further afield, over the beautiful Col de la Core in Seix (36km) the Kayak Club offers a similar package for those wishing to explore another river.