Castles wouldn't always have exposed stone on the interior walls. It was common to plaster ... Stone was also used on castle floors, but brick and hardwoods were just as common.

A 400-year-old stone wall once part of Edo Castle, discovered only last year at what is now the Imperial Palace in Tokyo, is likely the castle’s oldest existing remnant ever unearthed ...

OTSU--A 30-meter-long stone wall and a moat were unearthed at the site of the castle belonging to the 16th-century samurai general who betrayed feudal warlord Oda Nobunaga (1534-1582). The city ...