You can climb up to the Naranco sites or take the bus from Calle Uria, going towards the bus and train station, not the cathedral (opposite side of street from Corte Ingles and Mc Donald's) It leaves you right in front of the parking lot for the monuments. Take 30 minutes or an hour to look around and get back to the parking lot where you start walking in the same direction the bus was going (if your back is to the monuments, then walk to the right). This road will take you into Uccle where there's a bar, you keep going down that road and eventually, at a small chapel where you can self stamp your credencial, you join the Camino and those who walked from Oviedo. The path leaves the road there, you have to get on the grass. It's maybe an hour walk from the sites to the chapel.
(I don't know why the word climb appears underlined, but it's appropriate as it's quite the climb! Even by bus it's quite something.)
Bus is A2. It's the one that goes to the Centro Asturia.
Now, there is another way to leave the sites, a small road that starts behind the second monument, the one further up the hill. It has a GR sign.
San Miguel de Lillo and Santa María de Naranco are two of the most beautiful pre-romanesque (i.e., 9th century!) buildings on any camino.
Depending on your walking distances, Oviedo - Naranco- Grado is certainly doable, but the Naranco sites only open at 9:30 in summer and 10:00 from October through March. That would make for a late arrival. (And I believe all is closed now because of Covid, so you would need to check on reopenings when you actually get there).
If you are coming from across many oceans and taking a jet lag day in Oviedo before stopping, walking up and back to the churches is a great way to get some daylight so your body can acclimate and you also get a bit of hill walking to prepare you for what’s to come on the Primitivo. From the Oviedo train station, it’s 3 kms up through pretty residential neighborhoods to the sites. You can also get a municipal bus but why waste the opportunity to walk?!
Another option is, as Tinca suggests, to make day 1’s destination Escamplero so you will have plenty of time.
The San Miguel de Lillo church was closed for two years while restoration work was underway, so it must be truly amazing now!
Stumbled on this older post; bumping it, now that we can plan our walks again! These churches are so remarkable, and very much worth folding into any Primitivo planning.
Here is a map for the last part - the route to walk to intersect the Camino, at Capilla del Carmen.
It's worth noting that a couple of hundred meters after Naranco, you will pass San Miguel de Lillo (2 on the map) - as Laurie's wrote makes clear, equally venerable and worth visiting:
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