Jilem is a village in Semily District, in the Liberec Region, Czechia. Jilem lies at 454 m above sea level, at the foot of the Giant mountains. The nearest city is Jablonec nad Nisou, 28 km to the west. Among the landmarks around are Trosky Castle (22 km), Valdštejn Castle (25 km) and Augustinian monastery in Vrchlabí (7.0 km). Among the natural features are Przełęcz Karkonoska (19.9 km) and Mumlava Waterfall (19.5 km).