Bishop's Palace is the second largest palace in Krakow (first is Wawel Royal Castle). This building served as the residence of Krakow's bishops starting from its opening in the 14th century.
Palace is most famous for having been the residence of Cardinal Karol Wojtyla from 1958 to 1978, which then became Pope John Paul II. During his visits to Krakow as Pope he often appeared in the 'papal window' in the evenings to address the crowds of his followers. To make this "special" window recognizable for tourists, an image of John Paul II usually fills the window. During anniversaries you will surely see the area festooned with flowers and candles.
Now the building itself is closed and not allowed for visitors, but the courtyard is open to tourists where you'll find an exhibit on the life of the Pope and the first monument of the pontiff, erected in 1980.