Lisbon Free Walking Tours - The Definitive Guide [+ Free Maps]. Walking tours are the best way to explore Lisbon, but the question is: How to find in Lisbon free walking tours that are 100% free? The answer: go on a self-guided walking tour. I’ve created 3 self-guided walking tours that you can follow to discover Lisbon, for free. Let’s see them! #portugaltravel #springbreak