This is one of the biggest trade and open-air events in Europe.
The tradition came from Medieval times, when the Dominicans had the privilege to organize trade in certain days during the year, all over Poland. The purpose of that was to convince people to participate in the celebrations of St Dominic’s Day on 6th August.
Nowadays it is organized every year in the summer for three full weeks. It is an enormous fair with thousands of visitors. In the dealers stalls you can find numismatic and philatelic collections, as well as handicrafts, haberdashery, valuable cloths and antiques. There are concerts, street theaters and performances, and of course there is plenty of food.
One can find an abundance of food stalls offering drinks, meat, potatoes and sausages. You will have a unique opportunity to taste some traditional Polish dishes, like e.g. pierogi (dumplings), bigos or farmhouse bread with lard and dill pickles.
See the map of all Tastes of Poland, with the location of Gdańsk: http://blog.polishorigins.com/2013/05/21/tastes-of-poland-introduction/