We need to spend some days in Lisbon (Portugal), also Sintra and the coast around that area. Are there any good places for urbex? We know Sintra is known for its palaces and mansions (some of them abandoned), but since it's an eerie location with lots of ghost stories, I'm not sure we would enjoy that kind of urbex. But if you have any ideas...

We are interested in old architecture, industrial complexes and abandoned state buildings, universities and the like, but anything interesting is more than welcome.

I read about the roman galleries under Lisbon (and I know they open for a day every year), that would be extremely interesting but probably impossible to get in. In Portugal we already visited some abandoned hospitals, hotels, thermal facilities, even an abandoned holiday complex.

Traveling a few KMs is not an problem, we have a car or motorbike.

PS: Some of the activities related to urban exploration might be a felony (like trespassing). Always ask the owners for permission before entering a place.