Dresden's cultural heyday came under the 18th-century reign of Augustus the Strong and his son Augustus III, who commissioned many of Dresden’s iconic buildings, including the Zwinger and the Frauenkirche. As Electors and Kings of Saxony, they have furnished the city with cultural and artistic splendor, and Dresden became known as the “Florence of the North” or the “Jewel Box” on account of its baroque and rococo city center. The controversial, devastating American and British bombing of Dresden in World War II towards the end of the war killed approximately 25,000 people, many of whom were civilians, and destroyed the entire city center. While the Allied firestorm leveled most of the city’s treasures, their contents were safely removed before the bombings and now take pride of place in Dresden's rebuilt museums. After the war, restoration work has helped to reconstruct parts of the historic inner city, including the Katholische Hofkirche, the Zwinger, and the famous Semper Opera. Since German reunification in 1990, Dresden is again a cultural, educational and political center of Germany and Europe. It is the capital of the Free State of Saxony. The economy of Dresden is one of the most dynamic in Germany, and it’s dominated by high-tech industries, often called as “Silicon Saxony”. The city is also one of the most visited in Germany. The royal buildings are among the most impressive buildings in Europe. The most prominent building in the city of Dresden is the Frauenkirche. Built in the 18th century, as a Protestant response to St. Peter’s Basilica, the church was destroyed during World War II. The remaining ruins were left for 50 years as a war memorial. The newly built Frauenkirche has charred stones from the destroyed church adapted with new stones as a reminder of the destruction from World War II.