One day
Start on the Old Town Market Square with the great Gothic town hall (climb the tower) and the Copernicus monument, then visit the Copernicus birthplace house and St John's Cathedral. Bake or buy gingerbread and have a pierogi lunch, walk the Vistula walls and gates and the Teutonic castle ruins in the afternoon, and take in the quieter New Town square. End with a cellar dinner and the lit brick town at dusk.