A very unique museum underneath Rynek Glowny (Main Market Square) is opening in Krakow. The museum was built on the site of an archaeological excavation that unveiled secrets of Krakow's evolution since its founding in the early Middle Ages.

Visitors can walk underground from the main exhibit area to other exhibit chambers over a glass-bottomed footbridge that allows them to see elements of medieval architecture and paving below. The corridor takes them past the Wealth Stalls and even older stalls dated from the 12th Century.

Some of the paving goes back to the time of Kazimierz the Great, the king who founded Krakow University in the 14th Century. The exhibits show the names of the streets reflected by the paving. In addition to remains of old pavement, the museum displays also old water pipes. The see-through footbridge is a concept that "makes this museum designed not up to the 19th-Century museum tradition but in a completely modern manner," Mayor Jacek Majchrowski said.