#4 train
Honestly, just get an Uber. They will drop you off within a few minutes walking of the ticket counters and gates.
You can take the 4 train at Grand Central, uptown to 161/Yankee Stadium
You have to go get a transit card and take the subway. there is a stop right across the road from the stadium do a little home work before you go so you can walk from grand central and pick up the subway you can google map it so you can get directions while you walk using your phone so you dont get lost. Hope this helps!!
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