Sugasan-ji Temple was originally called Ryuzan Daikoji Temple. At that time, it was a member of the Hosso sect of Buddhism, but later became a member of the Toyozan school of the Shingon sect of Buddhism. Sugawara Michizane was born in Kawanami Village near Lake Yogo and studied at this temple from the age of 6 to 11. In 889, the temple was restored with 3 temples and 49 monks, and its name was changed to "Omikisan Sugayama-ji Temple" after one of the characters of Sugawara no Mikoto. The temple was once again brought back to prosperity by Michizane. This temple was one of the most prosperous temples from the Fujiwara to Kamakura periods. According to the old records of Kofukuji Temple, it was a very large temple with 105 monks' quarters and more than 70 subordinate temples. The large zelkova tree that still stands in front of the temple gate is said to have been planted by Michizane, and is designated as a natural monument of Shiga Prefecture. The 7,000-odd scrolls of the Sung version of the Buddhist sutra were donated to Zojoji Temple in Shiba by order of Tokugawa Ieyasu, and are now designated as a National Important Cultural Property. Although the temple is currently without an abbot, the treasures of Sugasan-ji are on display at the Satobo Kozenkan at the foot of the temple.