different from a guided tour by a tour guide, an audio guide gives you more flexibility in differents aspects: flexible choice of the beginning of the tour; flexiblitiy during the tour itself (no need to follow exactly a given track). When you require deeper background information you should book a tour buided by a tour guide.
The tour par un audio guide vous donne becoup de flexiblité en rapport avec le temps de commencer le tour et le chemin en prendant lequel. You will be able to take advantage of the information plus professional information provided by the commander and a tour guide by a tour guide
With the audio guide you have the highest flexibility regarding the start of the tour and the route you take during the tour. If you need more detailed information, you should choose a tour guided by a tour guide.