2 and half hours (more or less) of walking from Firostefani to Oia, on the cliff. The view is spectacular. Not too many people use this path. either they don't know about it or they're too lazy to leave the swimming pools at the hotels. But it's one of the best things to do here. You have to trust me on this. You can't get lost. There's only one road. Try it if you happen to be around.