If you regularly forget exactly where you left the car in a busy car park or unfamiliar city, your iPhone can often save the location automatically.
When iPhone disconnects from your car’s Bluetooth or CarPlay system, Maps can mark the place as a parked car. You can then open Maps later and look for the parked car marker instead of retracing your steps.
The feature works best when Significant Locations and relevant Maps settings are enabled, and when the iPhone can tell that it has disconnected from a vehicle rather than an ordinary Bluetooth accessory.
You can also add a note or photo to the parked car location, which is useful in multi-storey car parks where the map pin alone may not tell you which level or section you used.
If the marker never appears, check Maps settings and make sure the phone is actually connecting to the car over Bluetooth or CarPlay during journeys.
It is a small feature, but one that becomes much more useful the first time you return to a huge car park and realise you cannot remember which row you used.