Hi! This is a strange question, I know, but one I really do need to know the answer to... I will be taking a roadtrip with my dad this summer and I normally do all the driving. However, driving through tunnels is really bad for my vertigo and I just can't do it, so we have to switch drivers when going through tunnels and need to kniow ahead of time if one is coming up, obviously. Can anyone tell me if and when we will encounter any tunnels on the highways?
The plan is to drive from Lisbon to Porto and back (potential stops are Cascais, Sintra, Nazare, Alcobaca, Coimbra, Aviero, Obidos)
If you can tell me about the tunnels, I will feel much better. If you have ideas for different stops or editing the stops on the list, I'd appreciate that too!
Thanks so much!
Joanna

You may also load down google.maps and enlarge the scale until you nwill see every tunnel, even the shortest one.

All the road tunnels I've encountered have been inside cities - Lisbon and Braga.
We drove through the cities that you mention (except Coimbra or Porto) in the winter of 2023 and did not encounter tunnels.

I´ve only encountered the Marão Tunnel tunnel through the Serra de Marão on the autoroute, A4, from Porto to Vila Real. It's 7.5 km long, the longest in Portugal and 3rd longest on the Iberian peninsula, but if you're not heading to the Douro on the fast toll road, you won't go near it.

I encountered several tunnels en route between cities, though I don't remember where. Neckervd has given you good advice.

Plenty of tunnels in Portugal, both inside and outside of cities.
I don't know Oporto well, but driving in Lisbon will be an issue for you, I guess.