| Six kilometres northwest of Foix, the underground river at Labouiche (April–May, Oct & Nov Mon–Sat 2–5.15pm, Sun 10–11.45am & 2–5.15pm; June & Sept Mon–Sat 10–11.15am & noon–5.15pm, Sun 10–11.45am & 2–5.15pm; July & Aug Mon–Sat 9.30am–5.30pm, Sun 10–11.45am & 2–5.15pm; usually a fifteen-minute wait; €7.40) is the longest navigable subterranean river in Europe. The visit consists of a barge trip lasting one and a quarter hours, along 1km of the river, 60m underground, to admire its stalactites and stalagmites. Twenty-five kilometres west of Foix, the Mas d'Azil was one of the first prehistoric caves to yield evidence of human habitation, but its most impressive feature is a magnificent 500-metre natural tunnel, scoured by the River Arize, which now carries the main road (the D119) from here towards Pamiers. Without your own transport it's not easy to get to as it lies 12km north of the Foix to St-Girons bus route: get off at Vic after La-Bastide-de-Sérou and take the D15. It's a pretty road, but without a lift it'll take a good two hours on foot. Failing that, four Semvat buses a day run from Toulouse. Secondary caves leading off the river cavern are the focus of historical interest; they were inhabited in prehistoric times for more than 20,000 years and used as a refuge by Cathars and Protestants in more recent times. As usual, the most important galleries are sealed off, though this hasn't stopped damage from road pollution, and those caves you can visit are interesting mainly for their sheer size (March, Oct & Nov Sun 2–6pm; April Mon–Fri 2–6pm, Sat & Sun 10am–noon & 2–6pm; May & June Mon–Sat 2–6pm, Sun 10am–noon & 2–6pm; July–Sept daily 10am–noon & 2–6pm; €6.10 including museum entry). A few tools, animal bones and other objects found during excavation remain on view in glass cases in the caves, but the best pieces are now on display in the attractive, sleepy village of LE MAS-D'AZIL, 1km to the north, in the Musée de la Préhistoire (same hours and ticket as the cave). Among other engraved tools and weapons, the museum's most outstanding exhibit is the beautiful carved antler known as le faon aux oiseaux, perhaps used as a spear-thrower. The best hotel in the hamlet is the Hôtel Gardet (tel 05.61.69.90.05, fax 05.61.69.70.27; €30–40; closed mid-Nov to mid-March), with a decent restaurant (menus from €10), and there's a municipal campsite (tel 05.61.69.71.37; closed mid-Sept to mid-June) a twenty-minute walk away. The best place to eat is Le Jardin de Cadettou (tel 05.61.69.95.23; closed Sat lunch, Sun eve & Mon), a homely restaurant with excellent menus of regional cuisine from €13.72, which also has rooms (€40–55). Alternate spellings:: France, Mas d'Azil, Mas d'Azil, Mas d'Azil
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