You leave Avilés through the Parque del Muelle, towards Avenida de Alemania, this is the first effort of the day as it requires climbing. From the top, you have to come down through a gravel road to the tourist spot of Salinas, which has one of the longest beaches in Asturias. From there you continue to Santiagu´l Monte, past the village of La Cruz.
Forests and villages accompany you until you get to El Castiellu/El Castillo, with its wonderful castle, in private hands nowadays. You can ignore the signs for pilgrims and continue to the beginning of Sotu´l Barcu/Soto del Barco, it is a nice walk.
In Muros you have to go down towards the river, cross it and access the town, with the Plaza Marqués de Muros, where you will find the church of Santa María and the town hall. You can visit the old palaces of Valdecarzana and Vallehermoso although you can also see them the next day as they are on the way out towards the next section.
In Muros you will find the Playa d´Aguilar, from there you start the Ruta de Los Miradores (Route of the Miradors), an area with high cliffs that takes you to the mouth of the River Nalón. Barges used to sail down this river loaded with coal coming from the mines. There are tables, benches, huts and fountains along the way.