Kraków’s oldest church sits not unlike a lost orphan at the southeast corner of the market square - a mad mix of pre-Roman, Roman, Gothic, Renaissance and Baroque architecture. The earliest parts of the building date to the 11th century, thus pre-dating the Rynek and explaining its seemingly random position within it. St. Adalbert had his own cult following at the time, which explains how it managed to survive. A look inside the small interior is interesting, not least because the floor sits some two metres below the surface of the main square. There's also a small, uninspired, Polish-only exhibit hosted by the Archaeological Museum about the history of the market square (a poor man's version of the Rynek Underground Museum, and open May 4th-Sept 30th only, 10:00 - 16:00, Tue 10:00 - 14:00, closed Sun; admission 4/2zł, Mon free). The best way to experience the church is during the frequent concerts by the Royal Chamber Orchestra.