I had to circle Hamahiga Island twice before finding the narrow, earth road. An hour’s drive from Naha, a sign made from sliced bark pointed to Takaesu Seienjo, a salt factory hidden behind clumps of ficus, deigo and subtropical broadleaf trees.
According to records, commercial salt production in Okinawa began in a tidal wetland near Naha in 1694. In a 19th-century guidebook on diet therapy, a physician to the Ryukyuan royal court named Tokashiki Pechin Tsukan claimed that salt, known in Okinawan as “māsu,” “removes toxins, purifies qi energy, and expels lung diseases.”