I really loved the 516 Arouca Bridge, high up in the mountains. The air was crisp and fresh, just like walking on the Hehuan Stream Trail. There were very few tourists, and the Paiva Walkways were incredibly easy and comfortable to walk on; you don't get tired even after a long walk. That day, I also met many solo female travelers from different places: Michigan, the Philippines, and Kenya. They were all traveling alone and had already visited many places. We chatted happily along the way as we hiked. The Aveiro river cruise has a charm that combines Venice with a Wild West town. Although it's a bit far from Porto, it's truly worth a visit! We all thoroughly enjoyed this day of mountains and sea.