From Seattle to Singapore and Helsinki to Montevideo - I am a definite fan of Hop On Hop Off busses and their multitudinous clones and variants. Time allowing, I ride the entire circuit once, stay on the bus for a second trip, hopping off to explore a given stop, and hopping back on for the next point that stirred my interest. Prices range from port to port but are usually in the $45 to $55 price range. Routes range from 45 to 90 minutes and most use headsets to access a wide range of language options and most busses hit each stop every 30 to 60 minutes.. Some tickets are good for two days - others offer bargain prices for the second day. By the time your second ride is run - you could deliver the presentation yourself - and are wiser than you were (getting wiser is what traveling is all about for me).