Start: The hike starts at the top station of the Planpraz cable car.
(S/E) Climb the wide slope, passing the paraglider departures on the left.
(1) At the Parsa chairlift, turn right on the uphill path to a junction of two trails.
(2) Leave the TMB GR® on the right and follow the path slightly uphill on the left. Continue to the Col du lac Cornu. You'll enjoy an exceptional panorama of Mont Blanc, the Aiguilles de Chamonix and Lac Cornu.
(3) Continue for a few metres, leaving the path leading down to the lake, and turn right at an intersection.
(4) Take the right-hand path. From this intersection onwards, a few tricky passages through scree. Pass under the Aiguille Pourrie, to reach the Col de la Glière (view of the Fiz mountain range).
(5) After the pass, pass through huge scree to a new intersection.
Turn left and follow the path to the top of the first Lac Noir. Continue straight on to the second, less-frequented lake. On the way down, you'll need sure footing and the use of your hands. Reach the edge of the lake (bathing possible ... in cold water).
(6) To return, take the opposite route to the (S/E), then take the Planpraz Télécabine.