Софія Київська, or Saint Sophia Cathedral, is a historic architectural masterpiece located in Kyiv, Ukraine. Built in the 11th century, it is one of the oldest surviving churches in the country and a UNESCO World Heritage Site. The cathedral is renowned for its stunning mosaics and frescoes, which showcase Byzantine art and culture. The cathedral serves as a symbol of the Christian faith in Ukraine and has played a significant role in the country's history. It was originally constructed during the reign of Yaroslav the Wise and has undergone various restorations over the centuries, preserving its cultural and historical significance.