Access: from Léoncel, take the D199 for about 9 km to the Col de la Bataille, where you can park at the side of the road after the tunnel.
(S/E) Follow the track (GR®93) which heads off horizontally to the right, southwards, at the foot of the Roc de Toulau.
(1) At Pas du Gouillat, in a left-hand bend, leave the trail (GR®93) and continue south on the path that follows a fence, towards "la Tête de la Dame" and "Les Sarnats". Pass the Croix d'Ambel, leave the path on the right towards Omblèze and continue to the Tête de la Dame (1,506 m).
(2) Continue to follow the ridge and ignore the paths that lead into the park. Pass the Pas de Rouisse, a shepherd's hut and a water reserve (Pas d'Ambel), then climb back up to point 1492 before descending to the Pas de la Ferrière, the western end of the hike, marked by a fence and a gate.
(3) Turn almost completely around and take the path (GR®93) heading south-southwest, which runs horizontally along the edge of the woods. Ignore the path that branches off to the left (dotted line on the IGN map) and continue slightly further downhill towards the west, crossing a wooded area to reach the Pierre de l'Ours.
(4) Leave theGR®93and continue along the small path downhill, below the Pierre de l'Ours, through the woods. Cross a track and descend to the Tubanet refuge.
(5) Follow the track south for about 100 metres, then take the path (GR®93) that branches off to the right through the woods. This path joins the Ambel mountain pastures further down, enters the park and follows the edge of the woods. Halfway down the slope after the valley, it turns right and continues more horizontally through the woods, turning into a small track. In the next valley, take the most marked track that branches off to the right (GR®93) as it climbs. Continue straight ahead when you reach the next valley to reach the Ambel refuge.
(6) Continue along the path (GR®93) that you left to go to the refuge. Pass the water reservoir used to water livestock, go back up into the woods, then rejoin the track you took at the start at Pas du Gouillot.
(1) Turn right to return to the Col de la Bataille (S/E).