Azusa River
The Azusa River is a central feature of the highland valley of Kamikōchi. It originates on the steep slopes of Mt. Yari (3,180 m) and flows through the valley, passing beneath the iconic Kappa Bridge. As it heads south, the river forms the scenic Taishō Pond. It gathers momentum as it plunges through the valley, then spreads out to form Lake Azusa at the Nagawado Dam.
The river is said to take its name from the azusa tree (Japanese cherry birch), which was prized for bow-making. The river basin has been a center for farming and forestry since ancient times. In addition to supplying residents with fish and drinking water, the river has supported numerous industries along its downhill course to Matsumoto. For Kamikōchi, the Azusa River provided a route for floating the region’s valuable timber to city markets. It also aided the cultivation of mulberry trees, the leaves of which feed silk worms for silk production. About 15 kilometers downstream from Kamikōchi, local girls operated river-powered machinery that unwound silk cocoons into useable strands, then wove them into raw silk thread. Residents claimed that drinking the pure mountain water of the Azusa gave these silk workers their fair skin. At the end of the nineteenth century, mountaineer-clergyman Walter Weston (1861–1940) wrote of the river’s crystal-clear waters and white-pebbled banks, and spoke of buying a dozen freshly caught fish from an Azusa River angler to feed his men as they climbed Mt. Yari.
Today, the river is synonymous with Kamikōchi. Tourists and alpinists often pose for photographs beside its rushing waters at Kappa Bridge, the setting for Akutagawa Ryūnosuke’s satirical novella Kappa. The hotels and restaurants that line its banks offer customers views of a river that has changed little since the days of Weston’s sojourn.