The city four metres down

The Market Square measures 200 by 200 metres and has stood in the same place since 1257. But not at the same level. For centuries the inhabitants dumped rubble, ash and refuse here, paved the square anew, and the new layers covered the old. Today's square lies about four metres higher than the square of Casimir the Great's time.

We only really learned this between 2005 and 2010, when archaeologists dug up the eastern part of the square. They expected a few foundations. They found an entire medieval town: paved lanes, workshops, merchants' stalls with their scales still in place, water pipes made of hollowed trunks and, beneath St Adalbert's church, a cemetery with the graves of so-called vampires, buried face down with stones on their chests so they would not rise.

In 2010 the Rynek Underground opened here, one of the most interesting museums in Poland. You visit it exactly at the level of the medieval street, between the original walls of the stalls, while overhead, through glass ceilings, you see the legs of people crossing today's square. Mist, light and projections recreate the market of seven centuries ago, and the cases hold things people lost back then: merchants' lead seals, coins from all over Europe, dice, a child's shoe.

The most moving exhibit is the scales. The Great Scales stood in the middle of the square, and every item of goods entering the city had to be weighed and taxed on them. They made Kraków a rich city. Today their outline is marked in the paving of the square and their foundations can be seen underground.

A tip: tickets are sold for a specific hour and often sell out days ahead, especially in summer. Tuesday is free, and therefore the hardest. The entrance is in the Cloth Hall, on the St Mary's side.