This Trail is divided into three areas:
WALK BY THE PATH FROM LANUZA TO PANTICOSA
This is the section of the path that is not tarmacked. It passes through hay fields, thickets with many different kinds of shrubs (in particular the blackthorn, the berries of which people use to make the drink pacharán (a type of sloe gin), groves of oak trees (Portuguese oaks), of wild pine, of fir trees and broad-leaf trees.
You can look for sea buckthorn (Hippophae rhamnoides), a species unique to the Iberian Peninsula. It is used in gardening because of the pretty colour of its orange berries. This walk is also worthwhile because of the scenery; just before you get to Panticosa there is a phenomenal view of the Valley.
LA SARRA PATH
On the road from Sallent to Formigal, take the turn-off to La Sarra (you can leave the car at the dam). All around here you can see species of mountain and rock plants and trees, as well as those that live in the woodlands at the edge of highland meadows. There are birch groves, small areas of peat bog with typical peat land flowers: Primula farinosa, globe flowers, Eriophorum or cottongrass and Menyanthes trifoliate (also known as bogbean). However, it is not easy to find sundew (a carnivorous plant) as the mountain behind, La Foratata, is predominantly limestone.
For siliceous species we recommend you go to the area around the Resort Balneario at Panticosa, where there are other groups of flowers that do not grow in limestone areas. If you are visiting in the late spring you can ask about a rare and pretty orchid, in danger of extinction, that grows in the area: the lady’s slipper (Cypripedium calceolus).
ON THE FRENCH BORDER
This route starts on the left-hand side behind the businesses at the dam. On this walk you will come across a lot of different kinds of flowers, all mountain or highland species, and that are rare and endemic, etc
Climb the crag on your right and you will end up on the French side of the border, on the road. This is a hike that should be done slowly. There are wetlands, pools and ponds, rocky habitats and shady ones, entrances to old mines and scree. In between some of the big rocks, you will find the rarest plant species. You can also see meadow and bog species, and if you search among the rhododendrons you can even locate the rare orchid, Pseudorchisalbida. Some of the more interesting species that you can come cross are: fritillaries, snowbells, Salix pyrenaica, moss campion, the pasque flower (Pulsatilla), rock jasmines (Androsace), mountain avens (Dryas octopetala), the Pyrenean lily (Liliumpyrenaicum) and numerous orchids.
Remember, the French side of the slopes is in a National Park. As a result there are some limitations that you should be aware of, for example if you are talking dogs, etc.