... Alternate Visitor Parking Area: San Martin Center Parking Garage . If no metered spot is available on the North Visitor Lot (formerly Lot A), the visitor may be able to find parking within the Visitor section of the San Martin Center Parking Garage. ... There are currently three locations that provide parking for visitors driving to STScI-sponsored events: the Inn at the Colonnade (pay lot); the JHU Eastern lot (free parking), and the JHU Valley Center garage (pay lot with limited availability). ...