Warsaw Old Town
My first stop in Warsaw was Old Town. Old Town was meticulously rebuilt following the almost complete destruction of the city at the close of WW2. The Royal Castle was also wholly reconstructed, recreating what had been previously down to the most minor details. The most stunning aspect of the castle is the beautiful inlaid wood floors that surpass any other wood floors I've seen.
I've visited other places that have reconstructed monuments that were destroyed and wondered if a reconstructed monument is just a diminished echo of the original but lost structure. The combination of how well Old Town was reconstructed and the vileness of war crime that was the destruction convinced me that rebuilding was the best outcome. The rebuilding of Old Town is a lasting symbol that the Nazis lost.