The starting point is situated about 3 km from the village of Montgaillard, on the D28 road leading towards Orignac. You can park at the four-way junction, at a place called Cap de la Serre, near the motocross route.
(S/E) You might want to pop over and take a look at the ponds near the crossroads beforehand; you might be lucky enough to spot a few frogs or newts there. From the crossroads, take the dirt track that climbs southwards into the woods.
(1) Shortly after leaving the woods, take the path on the left at the junction: you can first take a short detour of about twenty metres to enjoy a wider view of the Pyrenees mountain range. Head back into the forest and pass close to a cluster of old chestnut trees, then a conifer plantation. Then head down to the right through the scrubby undergrowth and arrive above the Prégnalède spring, which has been converted into a watercress bed. Continue along the path and then the track through the woods until you rejoin the D120 road.
(2) Walk up the road to the left for a few dozen metres, then turn right onto the path that leads into the woods.
(3) At the first fork, leave the path and take a narrow track on the left. This leads you a little further on to the Fontaine de Lassègues (or ‘Houn de la Sègues’ in Gascon), which is actually two adjoining pools resembling ponds that give off a smell of sulphur. This is a sulphurous spring once reputed to heal wounds.
After the spring, continue along the path until you reach a wide track. Follow this track uphill to the left to rejoin the road and the crossroads (S/E).