Osaka Castle played a major role in the unification of Japan during the 16th century. It is one of Japan's most famous castles. The castle grounds contain 13 structures which have been designated as important Cultural Assets by the Japanese government.

Military governor Ujichika built Yanagi-no-Mary during the Taiei era 1521-1528 for his son, Imagawa Ujitoyo. The original Castle of Nagoya, was located near the site of the later Ninomaru residence. Oda Nobuhide seized it from Omagawa Ujitoyo in March 1532. He immediately moved in and changed the name to Nagoya Castle.

Matsumoto Castle is located in the city if Matsumoto, in Nagano Prefecture and is within easy reach of Tokyo by road or rail. The keep (tenshukaku), which was completed in the late 16th century, maintains its original wooden interiors and external stonework. It is listed as a National Treasure of Japan.