 The site of the Ōmi Ōtsu Palace, the site of the imperial court under the Emperor Tenji (626 – 672) and capital of Japan from 672 to 794, is said to be in the Nishikori district of Ōtsu.The site is adjacent to the Ōmi Shrine and protected as a national treasure.Ōtsu was the site of at least four castles