The guide was fun and agreeable, but I don't think the city of Colon is such a "must-see". We took the Panama Railroad from Panama City to get to Colon, and after a few minutes, it loses it's kitschy charm and becomes a bit mundane. Colon itself is interesting to see the locks and canals. There's a few forts as well. You then need to drive back (which is a bit long) or you can hop on the train back to Panama City. So for us..it was just okay. No fault of the guide, though.