We have just spent four weeks in the US in September and used hop on hop off tour buses in New York, Washington, San Francisco, Los Angeles and San Diego. The Washington tour was my favourite. The tour guides on all of them are a wealth of knowledge and familiarise you with all the local sights, tips and little spots you might otherwise miss out on. I cant recomend them highly enough. I used to believe that these buses were corny and not worth getting onto, but I have now learnt the error of my ways and suggest you get your ticket early. Great stuff.
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