Europe - Road Cycling in Portugal?

Mountain bikes seem popular but does anyone know what the road scene is like? I'll be in the North for a couple weeks at the start of October and wouldn't mind being able to rent a road bike for a few days. My plans are flexible, so a rental place in Oporto, Coimbra, Aviero, Viseu or the Minho would all be of interest. Not interested in riding anywhere around Lisbon.

We just got back from two weeks in Portugal.. In the south it was quite hot. maybe the reason, we saw few cyclists about.. We traveled the entire length of the country... never saw so many cars with bike racks per capitia in my life... But, fewer road cyclists were to be found in relation to the number of bike rack..
We mostly saw a preponderance of road bikes.. Roads with wide shoulders seemed outnumbered by roads with inadequate shoulders... Much of the road surface was rough.. In the Algavre we saw some bike tours about.. We stopped at a monument at Sagres( at the point) It mentioned at beginning of a bike path the whole length of the Algavre..
Favorite town.. Coimbra. A Univ. town. Certainly bike friendly.. visit the Fado showcase.. The "A Capella." And the beer is good and food tasty but filling so watch the calories.

jemory.. Does appear the Portugese take their cycling seriously. We saw our first - Critical Mass like event in Lisbon... Second photo.. Bike marking the beginning of the Algavre bike trail at Sargares.
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