The Trenton Transit Station is a short walk from the DEP Building.
Take the River Line or NJ Transit
Free Parking at the Perry Street Lot
NJDEP will run a shuttle from the Perry Street lot to the DEP building during the morning of the Mapping Contest and those attending can park there free of charge and use the shuttle.
Other Parking options include
1) On-street meter parking
2) The Station Plaza Public Parking Garage (information and Rates: https://www.nexusparkingsystems.com/station-plaza-parking-facility.cfm)
3) The Merchant Street Lot operated by the Trenton Parking Authority in Trenton (hourly parking rate charged).
Both Station Plaza and the Merchant Street lot are a short walk from the DEP building, and there is an hourly charge for parking.