21. Nijo Castle 二条城 or Nijo-jo was completed in 1603 as the residence of the first Tokugawa shogun of the Edo Period. Even though the Tokugawa Shogunate moved its power base and capital to Edo Castle in Tokyo they maintained this Nijo Palace in Kyoto as a reminder of who was in control. The entire castle grounds are surrounded by stone walls and moats. The palace survives in its original form with separate buildings which are connected by zigzag corridors with 'nightingale floors' that squeak when stepped upon as a security measure against intruders.