Kōchi Castle  Following the Battle of Sekigahara in 1600, Kōchi Castle was constructed in what was then the province of Tosa. It was built by Yamanouchi Kazutoyo, who took control of the province after the Tokugawa victory. The castle was constructed as part of the move from Urado to the more defensible Otakasa (alt. Odakasa) area. Construction was begun in 1601 and was completed in 1611. Much of the original fortress burned down in 1727; it was reconstructed between 1729 and 1753 in the original style. The castle underwent major restoration from 1948 to 1959. Though no battles were fought at the castle, it is noteworthy because the castle is the original structure, and not a post-war replica. It is also the only castle in Japan to retain both its original "tenshu", or keep, and its palace, the residence of the local "daimyō". In fact, it is the only castle to have all the original buildings in the "honmaru", or innermost ring of defense, still standing. Two previous attempts were made to build castles on Otakasa Hill. Both failed. The first attempt was by Otakasa Matsuomaru sometime during the late Heian or Kamakura periods. The second was in 1588 by the conqueror of Shikoku, Chōsokabe Motochika. The area around the hill at this time was extremely swampy, due to the influx of alluvial sediments from the . Consequently, previous builders were never successful in establishing a permanent fortress on the site where Kōchi Castle stands today. As one of only twelve intact castles in Japan, Kōchi Castle was popularly called a National Treasure () before the 1950 National Treasure Protection Law (文化財保護法施) was enacted. After the law was passed, it was demoted to the status of Important Cultural Asset (). Kōchi Castle can be seen in the background of the animated film "Ocean Waves" (I Can Hear the Sea) by Studio Ghibli, during the class reunion scene. The castle figures prominently in the film "The Harimaya Bridge". Key scenes in the movie take place in the courtyard just inside the Oteman Gate, on the top level of the castle itself, and at the entrance to the castle grounds just outside the Otemon Gate. Two rivers, the and the Enokuchi River, form the outer moat of the castle.