From the refuge, head for the Peas pass, crossing the Venton torrent.
Follow the GR trail for 200 metres with the torrent on your left.
Go past a modest moraine and cross the mountain pastures in a semi-circle until you reach the South-West crest of Petit Rochebrune.
At about 2,850 metres, follow the same route which climbs the crest, or go down the rocky slope to the sources of the Venton torrent.
Pick up the GR again on the bank of the stream and follow it to Les Fonts Refuge.