Whether you get to keep your keys or not varies per airport parking provider and the parking form you have chosen. Handing over your keys isn't usually necessary if you have chosen Shuttle Parking, as this is a self-park option. In some cases, however, the parking provider may ask you to give up your keys for the duration of your trip just to maximise space in the car park and make car parking more efficient for customers, or to ensure security with regards to fire safety. Rest assured that your car will not be driven unless it is absolutely necessary to do so, and that your keys will always be kept in a safe until you return. You will always be able to see if you can keep your keys in the comparison overview of the parking providers.