Lyft or Uber would be the best way to get to Fenway. Otherwise I recommend taking the MBTA blue line(aquarium station) to the Green line Yawkey station stop.
Take the T. Driving is chaotic.
It's not super close, definitely not walking distance unless your sightseeing. Wouldn't be a long drive, or you could take the T from the aquarium.
My wife and i walked it. It was about an hour. Many shops to go in. Its a nice walk when the weather is good. And i did this 9 weeks after breaking 4 metatarsal bones in my left foot. I would not recommend it if you have kids. And uber is everywhere.
Definitely not easy walking distance. But a short subway or taxi ride.
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