Tōbu Kiryū Line

The line's distant origin lies not in passenger transport but in the stone trade. It grew out of the Yabuzuka Stone Material Tramway (藪塚石材軌道), a reorganisation of a quarry-and-stone business whose president was Toshizō Hazumi. The company laid a tramway between Ōta and Yabuzuka and at first moved its stone by human power, though it also carried pilgrims on occasions such as the founder's memorial day at the Daikō-in temple (Donryū-sama) in Ōta.

The Yabuzuka Stone Material Tramway Company was incorporated on 20 July 1909, and in May 1911 it opened a 610 mm-gauge handcar tramway between Ōta and Yabuzuka to haul stone blocks. To carry general passengers and freight it then applied for a light-railway licence; when the licence was granted in July 1911 the firm was renamed the Ōta Light Railway (太田軽便鉄道) that October.

Seeking to convert to steam operation, the company brought in Tobu Railway's managing director Denji Yoshino as its president and, with Tobu's capital, began rebuilding the line, eventually agreeing to transfer its railway business to Tobu. Tobu acquired the railway division of the Ōta Light Railway on 5 March 1913 (the stone division being renamed Ōta Stone Material), and on 19 March 1913 the route opened as the Kiryū Line between Ōta and Aioi, regauged to 1,067 mm and worked at first by steam.

Electrification of the whole line followed on 1 March 1928. In March 1932 the line was extended from Aioi to Shin-Ōmama — the station that would later become Akagi — giving the Kiryū Line essentially the form it holds today. Azami Station was added on 5 May 1937, and on 1 November 1958 Shin-Ōmama was renamed Akagi, the present northern terminus.

In the post-war decades the line was modernised in stages: automatic train stop (ATS) ground equipment was introduced from 1 April 1973 and train radio entered service on 1 October 1979. Freight operations, long a part of the line's traffic, were abolished on 1 October 1996, with the last freight run on 25 September.

More recent changes have reshaped the passenger service. From 18 March 2006 local trains began one-man operation and through services started onto the connecting Koizumi Line; station numbering was introduced across all stations on 17 March 2012; and on 14 March 2020 Azami Station was moved 0.2 km toward the Shin-Kiryū side. Today every train calls at all stations on the line, and it also carries limited express Ryōmō services that run through onto the Isesaki Line to and from Asakusa in Tokyo.

• 190920 July: the Yabuzuka Stone Material Tramway Company is incorporated.
• 1911May: the Yabuzuka Stone Material Tramway opens a 610 mm-gauge handcar tramway between Ōta and Yabuzuka to haul stone.
• 191118 July: a railway licence is granted (Ōta–Iwajuku, 2 ft gauge, human power); on 1 October the firm is renamed the Ōta Light Railway.
• 19135 March: Tobu Railway acquires the railway division of the Ōta Light Railway (the stone division is renamed Ōta Stone Material).
• 191319 March: the route opens as the Kiryū Line between Ōta and Aioi, regauged to 1,067 mm and worked initially by steam.
• 19281 March: the whole line is electrified.
• 193218 March: the line is extended from Aioi to Shin-Ōmama (the present Akagi).
• 19375 May: Azami Station opens.
• 19581 November: Shin-Ōmama Station is renamed Akagi.
• 19731 April: automatic train stop (ATS) ground equipment is introduced and brought into use.
• 19791 October: train radio enters service on the line.
• 19961 October: freight operations are abolished (the last freight run was on 25 September).
• 200618 March: local trains begin one-man operation, and through services start onto the connecting Koizumi Line.
• 201217 March: station numbering is introduced at all stations on the line.
• 202014 March: Azami Station is relocated 0.2 km toward the Shin-Kiryū side.