The main cathedral in Pereslavl-Zalessky is the simple but beautiful Transfiguration of the Saviour Cathedral. The single-domed, four-pillar structure was built between 1152 and 1157, making it one of the oldest surviving white stone buildings in Russia.  The cathedral's interior was decorated with frescos in the 12th century but these have not survived, although fragments are now on display in Moscow's State Historical Museum. Now the interior of the church is completely plain. The cathedral also previously held the 15th century Transfiguration Icon which is now on display at Moscow's Tretyakov Gallery. In 1945 the cathedral became a museum dedicated to Aleksandr Nevksy and today it remains the property of the Pereslavl-Zalessky State Historical, Architectural and Art Museum Reserve although there are occasionally discussions about returning it to the Orthodox Church.