If you are a baseball fan and in Boston, go to a game, period. I also recommend the tour of the park ($8).
Don't believe people that say most seats are obstructed or that the seat are unbearable. If you can't fit in the grandstand seat, which are original, you should be worrying more about your weight than how small the seats are. They aren't that small. And Fenway is so small that you are never that far from the action.
Don't drive to the game, take the T to the Kenmore stop.
There's a reason that all the new parks have copied various features of Fenway. Go see the original.
Pros: tradition, small park, atmosphere
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