Ken is correct. Also if you don't have a Charlie card then get a Charlie ticket easiest and quickest because Riverside only has Charlie card buying provision open occasionally so don't rely on it. Also I suggest use the map inside the train if you are ever in doubt again. It is in every D line above th windows near th celling. The easiest way to get to any where is Google maps. Feed in your destination, then choose public transportation as an option. Google has timings for the train as well as so it could tell you by exactly why time you could reach Fenway. If your destination is beyond Fenway you may feed that too, it takes into account all kinds of public transportation to help you reach your destination.
Fenway stop exists. Fare is $2.40 if a Charlie Card is used. Otherwise, you get a paper-like ticket from a vending machine for $2.90 (I think, pretty sure). Using credit card is easiest. You can use cash with the trolley driver but change is a problem.
I was gonna use the weekend pass, but 10.00 per person. That will be cheaper. And the Charlie cards are available at the station?
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