Uomidai Scenic Lookout
Before the age of radar and sonar equipment, the fishermen of Yashima used uomidai (“fish lookout”) observation points to identify schools of fish in nearby waters. This was done by looking for signs such as clusters of ripples, shadows, or flocks of birds. When a potential catch was spotted, its location was conveyed to boats waiting below so that their crews would know where to throw their nets. This was most likely done using flags, mirrors, or fire or smoke signals to avoid scaring the fish away.
Centuries earlier, the same lookouts were likely manned by sentries who kept watch over vessels passing between the islands of the Seto Inland Sea. From the seventh century onward, a mountain fort was built on Yashima as part of a network of outposts intended to protect the then-capital of Asuka (near the present-day city of Nara) from incursions by rival Asian kingdoms, mainly Tang China and Silla on the Korean Peninsula. No invasion ever came, and the sentry posts on Yashima were gradually repurposed for more peaceful ends. Four uomidai sites have been discovered on Yashima and turned into scenic lookouts, from which visitors can try to spot fish, birds, and boats traversing the Inland Sea.