The complex of buildings of the former gasworks in Wola is an example of industrial architecture characteristic of ... the first gasworks on the territory of present-day Poland before those in Warsaw ...

One big problem with Poland's beautiful medieval towns is that they get super crowded, particularly during the high season.

so they suggest visiting the Warsaw Uprising Museum or doing some research before you arrive. Others also recommend saving time to admire the architecture at the adjacent Supreme Court of Poland.