Special Krakow's tram line no. 0, which is serviced by historical trams, runs on each Sunday and national holiday, within June 12^th - September 25^th 2022.
The route is the following:

Each year, aside of historical trams running on the line no. 0, heritage buses service special lines on select dates. In 2022, this takes place on June 19^th, July 17^th, August 14^th and finally on September 18^th.