Check the Mets website there's a few different answers parking lot opens a few hours before but then the actual gates to get in the stadium I believe that is 2 hours before listed game time but again check the website for all the information.
2hrs prior to first pitch
Depending on the day of the game is usually 2 hours before the first pitch
Stadium gates open 2 hours before game time. Parking lots open earlier.
2hrs
2 hours before games
Its 2 hours before any game
Check website varying answers
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