Access: to reach the starting point, pass through the village of La Bâthie on the D990, near the N90 interchange, south of the town of Tours-en-Savoie. Take the D65 and climb up to the hamlet of Le Daru, passing through the hamlets of Le Fugier, Montesseaux, Lachat and Le Mondon. At Le Daru, turn left at a sharp angle and continue along a mountain road. Pass the Fenêtre 7 EDF building below the road, continue for 200 m and take the track on the left for 200 m to stop at the plateau with signs indicating Chargeoir de Briaré at an altitude of 1,425 m (car park).
(S/E) Chargoir de Briarè). Head north, following the sign for Biorges chemin VTT. Pass the paragliding take-off area to admire the view (beautiful viewpoint).
(1) Continue along the downhill mountain bike trail, crossing the carriage road.
(2) Continue along the downhill path (mountain bike markings). Cross the carriageway four times and continue until you reach the junction with a track near the bend in the carriageway.
(3) Turn right onto the track and continue to the end. Continue along the downhill path to the hairpin bend, then follow the path on the right-hand side down to the Nant Varin stream. Cross the stream (there is no bridge) and follow the uphill path. You will reach a track (signposted Trimpaz).
(4) Follow the track downhill to the left towards Le Bognion (signposted) and reach the hairpin bend.
(5) Follow the path uphill to the right, marked in yellow, signposted Soplat des Nants. After a steady climb, join the track (not shown on the map) and reach the bend in the track.
(6) Continue straight ahead following the yellow markings, ignoring the path climbing to the right. After about 200 metres, the path gives way to a trail. Reach the top of the first gully (torrent bed). Continue north-east along the trail. Cross a second torrent bed and descend slightly to reach a crossroads.
(7) Continue to the right. Pass by the remarkable fir tree below the path, cross a small stream and continue along the ascending path to reach the Refuge du Soplat des Nants (picnic area).
(8) Follow the track, which heads north-east and then winds upwards. Continue along the track, which is flat and heads south-west. Ignore the tracks branching off to the right and left to reach the junction with the paved mountain road. Continue along the descending road, pass the Chalets de la Montagne des Prés and reach the intersection with the track. Take a sharp right turn to return to the starting point (S/E).
Right from the start, it's not clear from either the map or the description that the descent via the mountain bike trail poses no major problems. When you reach the Nant Varin stream, which is more like a small torrent than a stream, don't look for a footbridge, as there isn't one. We had to turn back. To conclude, I recommend this hike after a drought of at least 20 years, when Savoie and Haute Savoie will be deserts, which will most likely happen... Patience...!!!!