From Boí along the road to Caldes (L-500) up to the parking lot of La Molina. The route of the otter starts at the left bank of the river, beside the Park’s information stand. Traditionally known as the trail of “Pago”, the itinerary follows the river up to Palanca del Pey (a small concrete bridge) where we are presented with two options: either to continue our way along the shady side or cross over to the sunlit side. If we chose the second option we will pass by the Hermit of Sant Nicolau, shortly before the two paths meet again. From here on, the route continues up valley, leaving behind Lake Llebreta and the Sant Esperit falls and ending up at the information stand of Aigüestortes.