To park easily, you should go to one of the 10 park-and-ride in Strasbourg.
The Relay + Tram rate is only 4.10€ for the day and allows you to benefit from a round trip by tram/bus for all passengers in the vehicle (max 7 people).
This is for sure the best option for cheap parking in Strasbourg!
The closest park-and-ride to the city center of Strasbourg are:
Rotunda – 5 min by tram
Dukes of Alsace – 8 min by tram
Kimmeri – 8 min by tram
Rives de l’Ar – 10 min by tram
Elsau – 10 min by tram.