The railway line traverses through the Kitakami Mountains,[1] running parallel to National Route 106 for most of its length.

[1] It was not until 1920, when Hara Takashi, who had become the Prime Minister of Japan two years prior and had been a native of Iwate Prefecture, made the decision to build the line.

[2] The extension of the Yamada Line from Rikuchu-Yamada up to Kamaishi was opened by 1939,[2] prior to the outbreak of World War II.

In November 1946, after the Pacific War, the Yamada Line was closed for a long time between Hiratsuto and Toyomane Stations due to wind and flood damage.

Ōshida and Asagishi Stations were temporarily closed from January until 15 March 2013 due to low passenger numbers during the winter months.

[5] On 25 June 2012, a Public Transport Security Council, which consisted of the representatives of four cities and towns along the Yamada Line, Iwate Prefecture, and other organisations, was convened in a meeting held behind closed doors to discuss the restoration of the remaining section of the Yamada Line between Miyako and Kamaishi.

[6] The meeting discussed measures to ensure the continuity of alternative forms of public transport until the restoration of the Yamada Line, which was damaged in the earthquake, and concluded that the restoration of the line would take a considerable amount of time, as there were many issues to be addressed in each area, such as ensuring safety and consistency with urban development.