We opted for the longer tour which cost 10 euros (note: cash only) and we found it gave us a quick introduction to the city. We did not rent a car so this was perfect for us. While you travel around, they play a pre-recorded tour in both English and French which was helpful. The longer tour covers the old city, as well as, heading out to Illes Sanguinaires while the shorter tour only covers the old city portion.
My only complaints about the tour: I wished there was more time stopping at Illes Sanguinaires (you only had 15 minutes and we were able to sprint part way there and sprint back). I don't know why one side of the train had this plexi-glass enclosure...wished it was open so we could take photos or the plexi-glass could be cleaned?
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