Johannesthal is a place, that before the Treaty of Saint-Germain belonged to Austro-Hungary and was situated in the administrative region Reichenberg.
Johannesthal was formerly part of the German Empire. In the German Empire, the place was called Johannesthal (Reichenberg-Johannesth.). The place is now called Janův Důl (Liberec-Janův Důl) and belongs to Czech Republic.