This is quite a long route. Though it can be made from Pineta to the summit in a single day, bear in mind that this might mean some fourteen hours walking. An alternative idea could be to sleep overnight at the Balcón de Pineta, either in a bivouac or in the nearby Tucarroya Mountain Hut (placed in the Brecha de Tucarroya or Tuquerouya). I had some communications ascertaining the possibility to camp in the Balcón de Pineta, but I'm not sure about the regulations of the National Park on this subject. Check them before considering the camping idea.
You have to get to the valley of Pineta, on the eastern side of Monte Perdido (see main page). Start walking from the Parador Nacional de Pineta
Pineta to Balcón de Pineta
Into the glacier
First thing to do is cross the river Cinca, following the sign posts to enter the National Park (the Parador is on the very edge of the Park). After crossing the river you will find a big dirt track leading to your right (northwest). Follow it. After some fifteen or twenty minutes walking, the track turns right when crossing a river and a wooden sign on its left side marks "Balcón de Pineta" and "Cascadas del Cinca". Quit the track and follow the marked path. It is a nice, though sometimes steep, walk up the walls of the circus lasting some three hours. After that time you will climb a scree slope known as "el embudo" and you will finally see the Cross of Gravalos and the north face of Monte Perdido. The Balcón de Pineta will open up before you.
Next thing to do will be a turn to the west (left), to face the north side of Monte Perdido. There are rocky steps, separated by the Glacier of Monte Perdido, to deal with. The lower one should be climbed by one of the two rocky couloirs seen in the lower picture to the left. It is quite an easy grade II climb where rookies might find useful to have a rope around. After that, you will find yourself on the Glacier and turn right (north-west) in search of the second step.
When you get to the Collado del Cilindro beautiful views (picture by Waspee) shall be below you. The only thing to do will be to come down to the Lago Helado (the lake below you) and join the couloir of the normal route.
It is essential to bring ice climbing equipment, at the very least crampons and ice axe. In winter time a climbing harness and rope can be extremely useful.