I like the part on the eastern side of Oviedo/Gijón better than on the western side. It is a bit hard to fill 7 days. but if you take it slow, enjoy all views and make swimstops, it's the most scenic Camino you can get. I would start in Unquera (in Cantabria at the border with Asturias) and take all the coastal alternatives. This makes the Camino a lot longer, but so beautiful and you are avoiding a lot of asphalt.
Day 1: Unquera - Pendueles 18,4 km (and stay in Aves de Paso if open)
Ruta From Unquera to Pendueles (Camino del Norte alternative) de Senderismo en Unquera, Cantabria (España). Descarga el track GPS y sigue el recorrido del itinerario del sendero desde un mapa. This is a much more interesting (but also much longer) alternative to the
Camino de Santiago. Almost...
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Day 2: Pendueles - Llanes (the original route) 16,1 km (and have time to explore the beautiful seaside town of Llanes)
Ruta
Camino de Santiago in reverse: Llanes - Pendueles de Senderismo en Llanes, Asturias (España). Descarga el track GPS y sigue el recorrido del itinerario del sendero desde un mapa. A walk along the beautiful Asturian coast from trainstation to trainstation. The Camino del Norte in opposite...
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Day 3: Llanes - Nueva about 19,8 km, combining these 2 routes:
Ruta A little stroll from Llanes de Senderismo en Llanes, Asturias (España). Descarga el track GPS y sigue el recorrido del itinerario del sendero desde un mapa. Just a little walk from the outskirts of Llanes to the beach of Poo de Llanes to get a glimpse of the stunning coast of Asturias...
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Ruta Poo de Llanes - Villahormes (along the coast) de Senderismo en Poo, Asturias (España). Descarga el track GPS y sigue el recorrido del itinerario del sendero desde un mapa. This hike goes from trainstation to trainstation. You can leave your car either at the beginning or at the end of the...
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(And then continue for the last 3,3 kms on the Norte from Villahormes to Nueva.)
Day 4: Nueva - Ribadesella 20 km
Ruta Nueva trainstation - Ribadesella trainstation (along the coast) de Senderismo en Nueva, Asturias (España). Descarga el track GPS y sigue el recorrido del itinerario del sendero desde un mapa. On this walk you'll discover the stunning Asturian coast in full glory! I did this walk in May...
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Note: you can now walk all the way along the coast from Nueva to Ribadesella. Look at these tracks how to continue on after area recreativa El Infierno:
Ruta Ribadesella de Senderismo en Ribadesella, Asturias (España). Descarga el track GPS y sigue el itinerario del sendero desde un mapa. Graba tu propio recorrido desde la app, sube la ruta y compártela con la comunidad.
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Day 5: Ribadesella - Colunga about 24 km
Use the northern half of this route to Vega to avoid the ugly outskirts of Ribadesella:
Ruta 'Entre playas' revisited, Ribadesella - Vega (circular) de Senderismo en Sebreño, Asturias (España). Descarga el track GPS y sigue el recorrido del itinerario del sendero desde un mapa. Quite a nice and easy walk, but you are almost all the time (11,5 kms) walking on (very) quiet asphalt or...
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Take the coastal part of this route for a splendid alternative to the boring asphalt between La Isla and Colunga
Ruta La Isla beach - La Griega beach (circular) de Senderismo en La Isla, Asturias (España). Descarga el track GPS y sigue el recorrido del itinerario del sendero desde un mapa. This is a beautiful walk in a diverse landscape. Through meadows and little villages, past the beach of La Griega, a...
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From here on I am a bit lost. Colunga - Villaviciosa is still quite pleasant (however count on asphalt and a highway around). But the stages around Gijón and Avilés are a lot less scenic (I can recommend both cities though).