If I were you? I would to drive to exit 22 Greensprings Ave. Park at the Falls rd light rail parking lot and take it straight to Inner Harbor....plus parking is free!!!
Yes, you should be able to park there and go to inner harbor. You'll have to pay ahead of time for the park and ride so there should be no cost to you the day of unless you buy something while at inner harbor. Please know that a park and ride simply means that you park and take one car to wherever you want to go. There is no transportation from a park and ride to a destination.
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