Ecrins trekking

Col de l'Aup Martin

8 h
Return trip
Return trip
20.5 km
Total Length
1247 m
  • By walk
  • Fauna
  • Pass
  • Top

Departure : Entre les Aygues, Vallouise

At an altitude of 2761 m, l’Aup Martin pass is the highest point on the GR54 Tour des Ecrins et de l'Oisans. The icy névé that remain until the beginning of spring or the slippery shale can make some stretches difficult.

"It is in the unstable scree around the pass that the two-flowered saxifrage has chosen to grow.  It is a small, rare, pink and white flower, whose petals are spread apart from each other. A very hostile environment for such a small flower!

Blandine Delanette, Warden for the Vallouise area.

Park at the Cascades car park, at the end of the road to the bottom of the Fressinières valley. Take the footpath to left at the end of the car park. At the first crossing, take the footpath to the left, GR54, cross the footbridge over the Onde towards Col de l'Aup Martin. Follow the cairns in the riverbed of the Onde to join the footpath that follows the Selle stream. This will take you to the pastoral hut of Jas Lacroix, which is next to a shelter for walkers on the GR54 trail. Continue on the footpath, which heads to the bottom of the valley, over a ledge next to a waterfall, then continues along the south slope on a ledge, sometimes between large stone walls, until it reaches a shale zone at the foot of the Aup Martin pass. The return trip can use the same route to get to Vallouise. The descent via Le Pas de la Cavale and Le Pré de la Chaumette enable you to continue on the GR54 to the Champsaur area. It is also possible to get to l'Argentière la Bessée via Le Pas de la Cavale and the Fournel valley.


Nearest SNCF station: l'Argentière les Ecrins (  L'Argentière les Ecrins / Vallouise by bus ( or 04 92 50 25 05) or taxi (Taxi Pellegrin 06 98 88 17 78 / Taxi Billau 06 08 03 45 90) Vallouise / Entre les Aygues: shuttle service to be reserved  36 hours in advance ( 04 92 50 25 05) or taxi (Taxis-Ecrins-Pelvoux 04 92 23 42 48 / 06 62 13 34 30).


In Vallouise, take the small road to the right of the church towards Le Villard and Puy Aillaud. From the Villard de Vallouise, go straight ahead on the small road that crosses the hamlet and continues into the Onde valley. Go past the Béassac chapel to reach the Entre les Aygues car park. Caution: The road leading to the car park is closed in winter and opens earlier or later in the spring depending on avalanche activity.

Information desks

Vallouise Park house

Information, documentation, models, exhibitions, screenings, product sales and works of the Park. Guided tours for school, reservation required. The new Park House opened in Vallouise since June 1, and offers visitors an interactive permanent exhibition inviting to explore the area and its heritage. A temporary exhibition space will allow a renewed offer. Finally, the device is completed by an audiovisual room to organize screenings and conferences Free admission. All animations of the Park are free unless otherwise stated.

05290 Vallouise

Website - Email - 04 92 23 58 08

Lat: 44.84641, Lng: 6.48839

This trek is within park center, please read access rules.

Clic for map interaction

On the way...
Silver birch

On the edge of the Onde, once you have crossed the footbridge, the stone footpath weaves its way between the birch trees. This tree is easy to recognize amongst all the others due to it thin white bark. Due to the tar that it contains, birch bark stays intact even after the wood has rotted inside. It was used as parchment and as tannin in boreal regions. In this area, the birch's young twigs were mostly used to make brooms.

Feuille de bouleau
Southerly burnet

These small moths that come out during the day, are part of thirty species of burnet in France. Their long wings are black or sometimes bluish and have red spots. Such bright colours are a warning of toxicity to their predators. Burnets are capable of extracting chemical components similar to cyanide from plants. They then secrete this poison through their mouth and joints when faced with danger

Zygène transalpine
Chamois ragwort

In June it impossible not to see these large yellow sun-like flowers on the edge of the path. Their greyish, fleshy leaves look like they have grown through a spider's web. At the end of July they are unrecognisable: the leaves turn green and no longer have the grey fluff. Once the flowers have wilted, they give way to a fluffy white seed head that is easily scattered by the wind. Our elders used to compare them to an old man's hair (senex in Latin) which lead to the French name "séneçon".

Séneçon doronic
Cypress spurge

This is also referred to as "milk herb" in relation to the sticky white liquid that flows when it is cut. This is a toxic, irritating latex. It is identifiable due to its thin soft leaves and its original flowers that change colour and group together in inflorescence. By looking closer, in the middle of a 'cup' made from two bracts, it is possible to distinguish a female flower which is reduced to a ball (ovary) on a long stem, and males flowers with a sole stamen and four crescent-shaped nectar glands.

Euphorbe faux cyprès
"Popeye" grasshopper

In the pastures, in August, tens of grasshoppers jump and then disappear into the grass with each of our footsteps. Amongst them, the most original is perhaps the gomphocerus sibiricus nicknamed Siberian grasshopper, due to its resistance to the cold. The male is also known as the "Popeye grasshopper" because of its 'muscled' front legs. Its green-brown colour might mean it would go unnoticed were it not for this anatomical detail and it long, consistent "cre-cre-cre-cre" ending with a couple of separate "cre" that it repeats in order to attract a female.

Gomphocère des alpages
Green alder

This bushy shrub grows in entangled thickets, which are a refuge to birds and chamois that are in search of coolness and quiet. It is a pioneer and not afraid of settling in poor, steep terrains. Its strong roots mean it can latch on where everything else slides. Its flexibility means avalanches slide over it as it bends under the weight of the snow. The male catkins dangle when they are mature showing the pale yellow of their flowers. The female flowers will bear characteristic fruit like small pinecones that are first green, and then brown that persist all year round.

Aulne vert
Black redstart

The black redstart has a grey crown, a white patch on its wings and a tan tail and rump. A lively and active common bird, it likes the rocky environments and constantly hunts insects in flight or on the ground. Perched on a rock or a stone wall, it gives out brief cries of warning whilst folding it feet. Its chatty song interrupted by "paper rustling" is characteristic. This partly migratory bird can be seen at high altitude during the summer but heads to the lower valleys for the winter.

Rougequeue noir mâle

In the summer, it is at the coolest times of the day that you are likely to see a chamois busy grazing. When the sun heats the valley, they prefer to lie in the shade of the green alders, or otherwise stay on the névés. Their hearing and their sense of smell are highly developped and makes it difficult to approach them. You will need binoculars to see them. If the end of their horns are curved, it's a male, a buck. Open horns, it's a female, a doe. If the horns are shorter than the ears, it's an 'éterlou', a young male chamois in its second year. Barely visible horns, it's a kid.

Chamois mâle dans le vallon de Celse Nière
Pastoral activity in the Selle valley, dale

Between l’Aup Martin pass and Entre les Aygues, the Selle valley is the communal pasture for Vallouise. During the summer, the pasture is grazed by a flock of sheep, a herd of cows, a few horses and the donkeys that accompany the shepherds. The shepherd's role is to not only keep and guide the sheep on the pasture with the help of dogs. She also nurses them, in particular to avoid foot-rot, a bacterial infection of the hooves that could spread to wild animals.

La bergère de Jas Lacroix
Monk's Rhubarb

Around the pastoral hut, monk's rhubarb forms an ocean of bright green. This species along with Good King Henry and stinging nettles have a love for ample manure. They therefore create vast fluffy carpets on the animals' resting places and around the pastoral huts where they stifle out most of the other vegetation due to its vigorous germination and the damp shade of its large leaves. On its stem, the flower heads that look like candles are made up of uncountable greenish flowers that, when mature, will become winged, three-sided brown fruit. The leaf petioles of this wild rhubarb, which are fleshy, juicy and tangy, can be used in cooking.

Rhubarbe des moines
The ibex, a survivor

In the face of danger, the ibex does not run away but takes refuge on a rock face where it thinks it will be safe. This strategy has enabled it to escape from land predators for thousands of years. However, it has proved to be inefficient against man since the invention of the crossbow or the rifle. As a result, the ibex was almost wiped out in the 19th century. The species owes it survival to Italy's protection in the creation of a royal reserve, that later became the Gran Paradiso National Park.

Quatre bouquetins dans le massif des Cerces
The alpine ibex

In 1995 several ibex were introduced into the Champsaur. Since then, their population has steadily progressed to the valleys of the massif. A small group of ibex spend the summer season on the cliffs of the Chanteloube valley that overlooks the Jas Lacroix hut, on the left bank. They are more often than not perched on the rock faces and are difficult to see but from the hilltop above the hut, you might be lucky enough to see one on the rocks with the help of a telescope.

Jean-Philippe Telmon anime une sorties observation des bouquetins
The pastoral hut and the walkers' shelter

The Jas Lacroix pastoral hut is where the shepherd lives during the mountain pasture period. This where she herds the flock to count or nurse the animals. To the right of the hut there is a shelter for walkers on the GR54 route. It is maintained by a volunteer from the valley. Please leave it in the state of cleanliness you would like to find it.

La cabane de Jas-Lacroix
White throated dipper

Stocky, short-tailed with a slender beak, it has a white patch from chin to chest and the rest of its plumage is ginger to slate grey. This is the portrait of this fantastic stream-loving bird. Standing on a large, half-immersed stone, it rocks with its tail out. Then suddenly it dives head first into the turbulent water. One of its features is walking upstream in the water in search of food such as small invertebrates that it uncovers by moving pebbles with its beak.

Astrantia minor

At the top of a thin and fragile, divided stem, four or five small, delicate white stars move in the slightest breeze. The astrantia minor's umbels brighten up the shady areas that it likes under the shrubs on the moors. Its fanned, finely serrated leaves at the end of a long petiole, do their best to emerge from the vegetation.

Common frog

After the glacial cross-cliff above the Jas Lacroix mountain hut, not far from the footpath leading to the pass, there is a small lake that is home to the common frog. This is the most common frog in the Alps. It can live up to 2800 m in altitude, a record! It has a chocolate coloured mask around its golden eyes.

Yellow (mountain) saxifrage

At the edge of the clear waters of the brook, a flowerbed of yellow stars catches the eye. When young, the flowers are male and only have 10 stamen and a large shiny disc full of nectar. Later, when the stamen have fallen off, they become female and two small nipples appear on the nectar disc, ready to welcome pollen from a younger neighbour. The small rare and protected apollo butterfly has chosen this plant to protect its eggs and feed its caterpillars.


This shrub does not venture much higher than the last trees where it constitutes the moors that cover the ground along with other shrubs. Its finely serrated, light green leaves, ever green branches and juicy, sweet, black fruit that turn your tongue purple, make it possible to distinguish it from its cousins. The berries are a true treasure of the mountains and are used for many culinary and medicinal purposes.


The Selle valley is the Vallouise communal pasture where breeders take their animals in the summer. The pasture is divided into sectors where sheep, cattle and horses graze. Each group moves according to the growth of the grass and they rarely mingle, if at all.

Alpine lady's-mantle

Lush foliage, five to seven elegant leaflets, simple inflorescence, this plant is also known as "satin lion's foot", and is common along the footpath. This nickname comes from the underside of the leaves. Its flowers are not very attractive to insects. It does not need them for pollination. Its seeds develop spontaneously, without being fertilised: this is called apogamy. Is this why it is used as an infusion by the women of the high areas in all fields of gynaecology?

Red ants

A mound of twigs abounds with life at the edge of the footpath. An anthill in full action. On average it will house 300 000 red ants. This sociable insect is the epitome of perfection. It has strong jaws for digging, cutting and transporting; antennae for communicating and orientating; three pairs of non-slip feet for getting about; compound eyes to see as with a kaleidoscope; a chitin armour and a reserve of formic acid with which to attack. A simple experiment: put your hand close to the anthill, without touching it. Let the ants react then put your tongue to your hand...formic acid!


Rampion is a pretty, blue flower. On the way up to the Aup Martin pass, it is possible to admire rampion in the prairies and rocky areas at high altitude. A small ball of shiny purple-blue petals and scruffy stamen, it is perched on the top of a short stem surrounded by short narrow leaves.


Along the footpath, the marmot makes the rambler jump with its high-pitched whistle. They live in families made up of a couple of dominant adults and subordinates from successive litters. Grooming, games and fights ensure the cohesion of the group and the respect for the hierarchy. All participate in the delimitation of the territory by urinated or defecating at the boundaries or by rubbing their cheeks against the rocks in order to leave their scent.


It illuminates the scree that the névé take their time to free. Nestled and sticking in the rock, it amazes walkers who admire its delicate foliage and pure white flowers in such a grey environment. How does it manage to produce such exuberant flowers in such a hostile environment though? Beneath the stones, it develops a network of roots that enable it to get vital nutriments from the waterlogged soil when the snow melts. It also produces pliable shoots that always find a place to latch on in the scree.


Altitude profile

Altitude (m)

Min : 1599 m - Max : 2735 m

Distance (m)



Get information on snow conditions over the pass from la Maison du parc (04 92 23 32 31) or the Vallouise Tourist Office (04 92 23 36 12).  If necessary, take cleats to get over the pass.  Please do not disturb the work of the shepherd and respect her privacy at the Jas Lacroix pastoral hut.

See also

  • Marks GR GR