Sources du Tarn and Pic Cassini

Leave the D20 to the left or right, depending on which direction you are coming from, and take the small road at the sign for the Hospital, 8 km away. This very narrow road does not allow you to pass each other outside the designated areas, so you need to drive very carefully. The last few dozen metres on reaching the Hospital are on a track where you can park in a number of places, taking care not to obstruct motorists continuing on to the Mas Camargues car park.

Markings GR® White and Red + PR® Yellow

(S/E) Take the track in the direction of arrival, following the signs for "Pont du Tarn 2.3 km".

(1) Keep to the left of the track, leaving on the right the narrow path that supports several GR® and is the route of the return journey. Continue straight ahead at the crossroads a few dozen metres further on, as far as the dirt car park just before the stone bridge over the Tarn. Head for the directional post next to a sign giving instructions about herds and sheepdogs.

Yellow markings on wooden posts

(2) Turn left onto the path that runs between a barbed-wire fence and the narrow riverbed, alternating between short, uncomfortable rocky stretches and flatter sections. Numbered posts mark the route, which on this section is part of a discovery trail. Reach a junction.

No signposting

(3) Bear left, ignoring the path to the right that leads back to Mas Camargues. Continue upstream along the Tarn through a vast moorland landscape, skirting a gentle summit on the left. The river, which is still just a small torrent, flows below in a series of cascatelles. Reach a large flat area and ford a solitary boulder.

(4) Go straight on without crossing it and climb up the wide, grassy, west-facing valley that shelters the springs of the Tarn, whose flow varies according to the season. Beware of the spongy ground in places and keep going until the emerging river is no more than a tiny trickle of water flowing beneath the grass and rocks.

(5) Backtrack to the ford.

(4) Cross over to the other side of the river without difficulty and follow the wide track that winds its way lazily upwards to join the Route Forestière du Mont Lozère. Follow the road to the right as far as the next signpost.

Wooden signposts

(6) Head right, following the signs for "Pic Cassini - Mas de la Barque". The slope is gentle as you cross the meadows, then straightens out before reaching a new level. The path finally climbs back up through a magnificent environment of hooked pines and granite boulders of all sizes to reach the foot of the metal pyramid marking the summit of Pic Cassini. This peak, only 19 m higher than its illustrious neighbour, Mont Lozère, offers an exceptional 360° panorama. A plaque commemorates the work of the Cassini brothers in the 18th century to draw up the first set of geometric maps of France.

PR® Yellow signposting

(7) Take the left-hand path towards Mas de la Barque. After a few passages over scree, find a wide path and enter the forest. Continue almost flat to reach the vast grassy esplanade of the Col de l'Aigle, which offers the most interesting views to the north.

(8) Keep to the same path, which then bends 90° to the left, curves on a level surface and then begins a slightly steeper descent to reach a large crossroads not shown on the IGN map but marked by a signpost.

(9) Turn right following the signs for "Mas de la Barque" and continue to the next junction. Head straight ahead towards the wooden sign indicating the Route Forestière de Malpertus, and walk up for a few dozen metres until you come to the next prominent post.

Marked by wooden posts

(10) Go downhill to the left, following the signs for "Mas de la Barque 2.3 km". Follow the narrow path through magnificent coniferous and deciduous undergrowth, which, according to the signs, supports a snowshoe trail. Wooden stakes mark the level of snow cover along the way. Continue until you reach a wide dirt track suitable for vehicles.

White and red GR® markings

(11) Turn right, go straight ahead at the crossroads and continue flat out following the track that emerges from the undergrowth and winds through the pastures. Continue to the next junction.

No markings

(12) Leave the track and turn left onto a path that crosses the footbridge over a small tributary of the Tarn and quickly rejoins a track as it enters the Bois du Commandeur. Turn right and follow this track, disregarding the departures on the left, to reach the beautiful site of the Pont du Tarn. This magnificent stone bridge is not Roman, as some writings sometimes suggest. It was built in the 19th century, admittedly in a "Roman" style, but it does not date back to that period. Be that as it may, the site is well worth a stroll and a stop in the shade to cool off and rest. It's also an ideal bathing spot in fine weather.

GR® White and Red signposting

(13) Take the bridge and follow the GR® again via a wide, flat track that you should leave quickly to the right: there is no signposting at this point. The end of the circuit is on a fine grassy track, then a path winding between dry stone walls in an open landscape.

(14) Go left, following the signposts, and quickly rejoin the original track.

(1) Go straight ahead to reach the parking area (S/E).

The access road to the hospital is dangerous because it is so narrow. The only place where you can pass each other is in the regularly laid-out spaces on either side of the road. So you have to be very careful. The difficulty really becomes a problem if you come up against a van.

The signposting is of good quality, supported by a large number of directional posts. Given their number, not all are mentioned in the description.

The path followed between (6) and (7) to get to the Pic Cassini is just one of the possibilities on the ground. There is another path to the right, more or less parallel, which leads to the peak.

There are no water points on the route. Bring plenty of water.

Hiking boots are recommended because of the rocky sections. Poles will also be useful.

Le Pont de Montvert is a very charming little village, and very lively in high season because it is a stage on the Stevenson Trail. As a result, there are a lot of hikers here and accommodation may be difficult.

Florac.