Rennzähn is a place, that after the Treaty of Saint-Germain belonged to Czechoslovakia and was situated in the administrative region Dvůr Králové nad Labem.
Rennzähn was formerly part of the German Empire. In the German Empire, the place was called Rennzähn. The place is now called Zboží (Dvůr Králové nad Labem-Zboží) and belongs to Czech Republic.