We’ll begin this walk in Lalastra. A 15-minute walk will take us to the abandoned village of Villamardones, after passing the mill and crossing the Purón River. Behind the church, we’ll find a path that, first through beech forests and then pine trees, leads us to the hermitage of San Lorenzo (40 minutes). We continue along the track, which, to the left, skirts the cliffs of Anderejo. We first reach the junction with the Vallegrull Trail, and shortly after, the turnoff that descends to Ribera (55 minutes). We’ll continue straight ahead, ignoring the previous option. Just a hundred meters further on, right behind the pine forest in front of us, is the bird observatory. With patience and binoculars, we can see several species, about which the murals in the hut provide information. Back at the pool we begin the descent to Villamardones along the hill to its right, and from here we will return to Lalastra along the path we already know (1h.30′).