Japan is ruled by a monarchy similar to Great Britain. Here the monarch is called the Emperor. In the center of Toykyo are the Imperial grounds. They consist of the Imperial Palace, Imperial Palace Plaza, the East Garden (which includes the Edo Castle), and the Kitanomaru Park. It’s spring here so the trees and flowers are starting to bloom. The Imperial Palace is not accessible to the public but the rest of the grounds are.
There are still Imperial Samurai (historic Japanese warriors) that were practicing in one of the buildings on the grounds. You can see where the Samurai of old use to stay on the grounds in a couple of the pictures.