Polish edition of Wikipedia was created on September 26, 2001; it is one of the 200 versions in different languages. It contains over 800 thousand articles and it is the fifth largest after English, German, French and Italian versions.

The two-day celebration will be held in Poznan under the slogan: "The impact of Wikipedia on the lives of Poles." Series of panels and conferences are planned during the event, including a meeting with the founders and the first Polish Wikipedia users - Krzysztof Jusitiowicz and Pawel Jochym.

The organizer of the event in Poznan is, founded in 2005, Association of Wikimedia Poland.

Polish Wikipedia was founded on September 26, 2001 by the specialist in internal medicine Krzysztof Jasiutowicz and the physicist Pawel Jochym. First entry was an article on the Titius-Bode law - the distances between the planets in our solar system.

Encyclopedia was created as an independent project under the name of Poland Free Encyclopedia Network and it was joined to the international Wikipedia in January 2002.