Mříčná is a village in Semily District, in the Liberec Region, Czechia. Mříčná lies at 431 m above sea level, 3.9 km from the Giant mountains. It has 582 inhabitants (2024). The nearest city is Jablonec nad Nisou, 25 km to the northwest. Near the border: Poland, 20 km. Among the landmarks around are Trosky Castle (19.4 km), Valdštejn Castle (22 km) and Kost Castle (27 km). Among the natural features are Mumlava Waterfall (18.9 km) and Przełęcz Karkonoska (21 km).