The official residence of the Emperor and Empress of Japan since Tokyo became the political and imperial capital in 1868. Located in what was once the inner section of Edo Castle, the seat of the Tokugawa shogun, this 1.15 square kilometer of prime real estate in central Tokyo is enclosed by walls and moats, making a glimpse of its residents impossible. Only on two occasions--January 2 (New Year) and December 23 (Emperor Heisei's birthday) do the Emperor and the Royal Family emerge and wave to the gathering crowd from behind bulletproof windows.