Description : The Matsumoto Castle in Nagano Prefecture is one of Japan's premier historic castles, recognized for its distinct black exterior, which earned it the nickname "Crow Castle." Constructed in the late 16th century, it is designated a National Treasure of Japan and is one of the oldest surviving castle towers. The castle is unusual because it was built on flat land rather than a hill, and its architecture is characteristic of the Sengoku period (Warring States Period). Japan.