My partner and I have taken this same company's hop on hop off bus tours in London, Dublin, and Rome. Usually it is a very good, solid tour company with great stops and a good tour. In Dublin there was even a live guide who was just hilarious. In Porto, it was horrible! The buses are falling apart, the seats were ripped up on both buses we were on, and the sound system barely works, we had to keep moving around to find two that functioned. The English track was horrible, it was much too quiet and the accent was almost impossible to understand. It was also very boring when you could actually hear it. She would start talking about buildings or sights or people without even explaining where they were (ie, left, right, centre, etc). It was very confusing and frustrating. In the end we gave up listening as the music in between was really annoying, the same track over and over again, anyway we couldn't hear or understand half of the tour so why listen! We noticed a huge gap between buses when we were downtown eating lunch, there was only one every 20 minutes or so, which is ridiculous for a hop on hop off bus tour in the main part of town.
The yellow bus tour looked much nicer. We passed them a few times and their buses looked newer and less crowded, I would give them a try if I had my time back.
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