The Old Mosque stands at the entrance of Rostuša, a short detour from the Mavrovo-area sights around Galichnik. Built in the 17th century, it is one of the region's more important historic mosques, with a simple square plan, wood-and-stone construction, and a single minaret. It is most worthwhile if you are already visiting nearby Duf Falls or Saint Jovan Bigorski Monastery.