This is the Zwinger Palace in Dresden.
It was built when Augustus the Strong returned from Versailles outside of Paris after visiting Louis XIV. The Neoclassical architecture here is different than the baroque style through the rest of Dresden.
To the right you can see the art museum called the “Old Masters Picture Gallery” where I spent the afternoon. They had many Raphaels, Rubens, Canalettos, and even a Rembrandt there along with an array of work from other northern Italians.