Yes there is a very large parking garage underneath it.
There is a parking garage below the mall where the aquarium is located and the aquarium can validate your ticket so that you won't be charged for parking.
Oscar, there is a parking garage that is located below the Marketplace. You can access this garage from North Washington Ave or Lackawanna Ave near the bus station. Remember to bring in your parking pass to have it validated for free parking!
Thanks! Your answer is awaiting moderation.