Park in front of the cross at the Col de Noirmont.
S/E) Head due east along the path opposite and, after 20 m, follow the path leading uphill to the right: marked with a Red Ring. Reach the Col du Chastel.
(1) At the junction, take the path on the right for a few dozen metres, then turn left to climb up to Le Chastel.
(2) Walk around the archaeological site, including the sacred basin and the southern dolmen, then return to the Col du Chastel.
(1) Opposite, follow the Red Ring markings again; this leads onto a tarmac road, which you should follow to the left to return to the Col de Noirmont.
(S/E) Just before reaching the car park, take the path leading uphill to the right, marked with a Yellow Triangle. Cross a forest track and continue straight ahead to reach the Pierre de la Roche.
(3) Walk around the site and climb the ladder to admire the view. Then continue to the forest track, which you’ll reach just before the Croix de la Bolle.
(4) Turn left to return to the Col de Noirmont (S/E).