From Academic Kids
Kokyo (皇居, Kōkyo) is the Japanese Imperial palace in the Chiyoda ward of Tokyo. After the Meiji Restoration and the removal of the Shogun rulers, the Imperial court moved from Kyoto to Tokyo and the former Tokugawa stronghold of Edo castle became the residence of the Emperor of Japan.
It was destroyed during the Second World War by bombing, but was rebuilt in the same style in 1968.
Most of the palace is generally off limits to the public, but the East Gardens are usually accessible to tourists. The inner palace is only open to the public on two days during each year, the Emperor's birthday and New Years (January 2).
The Kokyo is close to Tokyo Station.