This photograph is one of a series made by Charles Wildbore showing the construction of the Mangahao hydro-electric power scheme in the Tararua ranges east of Shannon. Shown here is the multiple cable suspension bridge during the construction of the lower dam – original No.1 Dam and No.1 tunnel. The Mangahao Power Station provides hydroelectric power and is situated near the town of Shannon. It serves Wellington, Horowhenua, Taranaki, Hawkes Bay, and the Wairarapa. After being delayed by the first world war construction began in late 1919 and the station opened in November 1924.