United States
Staggeringly cheap way of getting round - $15 for 7 full days - even timed. Connections between buses/subway excellent. Get into Boston/Cambridge for a few dollars from the airport. Machine at the airport.
All subway stations
The Go Boston Card is the perfect pass if you want to visit a lot of Boston attractions. The card can be purchased for 1, 2, 3, 5, and 7 day increments. Once you have purchased the card you have the choice of visiting every attraction you can think of in Boston and surrounding areas.
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