As above, you’ve just spent x days walking to Santiago.
Pretend you're from somewhere else and slow down and smell the roses.
A Spaniard in your position would probably just have lunch.
.....or for good value silliness you could take one of the many coach tours from Santiago and explore the local countryside...including the Cabo at Finisterra and then on to Muxia....and other places.....
I think you’re overestimating the 20%, but he could stick to the road in some sections. There is a solid white central line which indicates the skateboard lane. In Spain it’s traditional for car drivers to sound their horn and shout a greeting...
If they do Fisterra - Muxia - Santiago and want a compostella don’t forget to get a stamp in Lires otherwise they might have issues at the pilgrims office.
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