For archeologists the city is a find, because in no other city in Russia have as many old buildings and art objects been preserved. During the time of the Mongols it even served as the center of the Russian empire and the seat of the grand duke. It was only under Ivan III that Russia annexed Novgorod. The ancient Byzantine Cathedral of St. Sophia is the center of the town and possibly the oldest building in Russia. The Yaroslav Court is all of what is left of the early palace complex of the Novgorod dukes. Not far up the road is the openair museum of wooden architecture with beautiful wooden churches and peasant houses from around the region.