The Ōoku (大奥 great interior) refers to the harem of Edo Castle, the section where the women connected to the reigning Shogun resided. Similar areas in the castles of powerful Daimyo were also referred to by this term. This included the shōgun's mother, wife, and concubines. Rumored to house several thousand women, including maids and servants at one point, the Ōoku was, as much as any other part of Edo Castle, a focal point of political intrigue for the Tokugawa shogunate. Later, a second corridor was built as the escape route against disasters such as fires or earthquakes.