The subject of the article is an urban legend whose basic principle is the combination of fact and fiction. The main point of the work is the analysis of an Old Prague tale tied to the U Křížku (At the Cross) house in Martinská St. in Prague.
Václav Hájek of Libočany incorporated its main protagonist, Jiří Šverhamr, into Czech history and it gradually became one of the important parts of Prague legend and the urban history of Prague as such. The article outlines the genesis of the account of Šverhamr's death for the fateful seal over time, especially the interesting update potential this tale had at the time of growing Czech-German antagonism.