The Fourth Battalion, the Village of the Blind
Chaharbrug Village is 35 km west of Esfarayen in North Khorasan Province. The village has about 1,000 people, of which more than 90 people are blind. It seems that from about 30 years ago, the problem of blindness in this village has spread and even some of its inhabitants have left the village. Experts say the cause of this incident is genetic variation and family marriage among the villagers.