Parking in the centre of the town is payable.
There is a gate at the entrance, where you must pay at departing from Piran.
You can park your car at the parking place Fornace at the entrance to Piran. Then you can walk to the center or take the free minibus.
Piran has a special traffic regime valid the whole year. Since Piran is a very small town and it has very little parking space, several parking place are
located at the entrance of the town. I suggest you to leave the car outside Piran on the organized parking place. You can the enter the city by bus which is free or you can take a walk 10 min. If you mange to enter you can only park on Tartini square.