01 / Haneji River Monument
Sai On studied the river's flow by feng shuiand rebuilt it in 3 months with about 100,000 people.

In 1735 Sai On, a Sanshikan minister of the Ryukyu Kingdom, began a major rebuilding of the repeatedly flooding Haneji Okawa River. The Ministry of Agriculture, Forestry and Fisheries says he surveyed its flow by feng shui and finished in 3 months with about 100,000 people. The Kaiketsu Haneji-gawa Hiki monument, raised by farmers, is a prefectural historic site.
- Work began in 1735
- About 100,000 mobilized (Ministry of Agriculture, Forestry and Fisheries)
- River about 6 km long
- 1969: prefectural historic site
