To reach the start of the hike, take the Roya Valley (D6203) and at Saint-Dalmas de Tende, head towards Lac des Mesches and the hamlet of Castérino. In the hamlet, continue along the narrow road until you reach marker 394, just after the sheepfold on the right. There is a car park with around 20 spaces.
(S/E) Marker 394: go through the gate and follow the wide track on the left overlooking the Ruisseau de Valmasque until you reach marker 393. Allow around 30 minutes.
(1) At the sign indicating "Le lac 2h", turn right and cross the stream on the small footbridge. The location is magnificent and very pleasant. The hike really begins here. The trail climbs steadily but without difficulty until the final steep section. The trail is direct and there are no intersections.
(2) The steep section is more impressive than difficult. It took us 10 minutes to complete this section. At the top, you arrive at a plateau that leads to the foot of the dam. Continue for a few more metres to reach the lake.
(3) The return journey follows the same route back to the car park (S/E).