You leave Penacova behind with the Mondego still nearby and a long day ahead. This is a stage from the lead-up: not an official part of the route, but well walked. The official starting point is Viseu.
It’s not the altitude that makes this stage hard. The highest point stays low. It’s the repetition: up, down, and up again. That adds up in your legs. With around 30 kilometres and almost 9 hours on the clock, it’s mostly about keeping to a steady pace. Start gently and keep it gentle. Carry enough food and drink, and plan your breaks in advance. That way you’ll arrive in Santa Comba Dão with something left in your legs.