Myōkō Haneuma Line

The route is one of the oldest in the region. On 15 August 1886 the government railway opened the Naoetsu–Sekiyama section as the first railway in Niigata Prefecture, with stations at Naoetsu, Takada, Arai and Sekiyama. On 1 May 1888 the line was extended onward from Sekiyama to Nagano, with Taguchi Station opening at the same time, and on 12 October 1888 the long corridor between Takasaki and Niigata was given the name Shin'etsu Line under the government's railway-line naming scheme.

Over the following decades intermediate stations were progressively added along the Naoetsu–Sekiyama stretch. Nihongi Station opened on 1 May 1911, and the Wakinoda signal post, established on 1 November 1918, was upgraded to Wakinoda Station on 15 August 1921. Kasugayama Station followed on 26 October 1928, Kita-Arai Station on 15 July 1955 and Minami-Takada Station on 10 December 1961, filling in the line's present pattern of local stops.

Electrification came relatively late: the Nagano–Naoetsu section, which includes this line, was electrified at 1,500 V DC on 24 August 1966. On 1 October 1969 Taguchi Station, near the foot of Mount Myōkō, was renamed Myōkō-Kōgen, the name it still bears as the line's southern terminus. In the late 1970s the line suffered a major natural disaster: on 18 May 1978 a debris flow from the Shiratagiri River struck the Myōkō-Kōgen–Sekiyama section, collapsing an embankment, and the line was repaired and reopened on 6 September 1978, with a truss bridge originally fabricated for the Ōfunato Line pressed into service as a new Shiratagiri River bridge.

With the breakup and privatisation of Japanese National Railways on 1 April 1987, the Shin'etsu Main Line, including this section, passed to the East Japan Railway Company (JR East). The most significant change of the JR East era came in preparation for the Hokuriku Shinkansen: on 19 October 2014 a new alignment around Wakinoda was brought into use and the station was relocated about 120 metres west, to sit alongside the new Shinkansen station then under construction.

The line as it exists today was created on 14 March 2015, when the Hokuriku Shinkansen was extended from Nagano to Kanazawa. The parallel Naoetsu–Myōkōkōgen portion of the Shin'etsu Main Line was transferred from JR East to Echigo TOKImeki Railway and renamed the Myōkō Haneuma Line, while Wakinoda Station was renamed Jōetsumyōkō to mark its role as the local interchange with the Shinkansen. JR Freight retained access as a second-class railway operator for through freight traffic.

Under Echigo TOKImeki Railway the line has continued to evolve. The sightseeing train "Echigo TOKImeki Resort Setsugekka" began running on 23 April 2016, and on 7 April 2017 operational control was separated from JR and merged with that of the company's other line, the Nihonkai Hisui Line. Successive timetable revisions reshaped through services with neighbouring lines, including a March 2018 revision that adjusted through trains with the Shin'etsu Main Line and added services from the Ainokaze Toyama Railway and Nihonkai Hisui Line. On 14 March 2026 Myōkō-Kōgen Station began accepting the Suica transport IC card, usable there only on the connecting Kita-Shinano Line.

• 188615 August: the government railway opens the Naoetsu–Sekiyama section as the first railway in Niigata Prefecture; Naoetsu, Takada, Arai and Sekiyama stations open.
• 18881 May: the line is extended from Sekiyama to Nagano; Taguchi Station (later Myōkō-Kōgen) opens.
• 188812 October: under the government's railway-line naming scheme, the Takasaki–Niigata corridor is named the Shin'etsu Line.
• 19111 May: Nihongi Station opens.
• 192115 August: the Wakinoda signal post (established 1 November 1918) is upgraded to Wakinoda Station.
• 192826 October: Kasugayama Station opens.
• 195515 July: Kita-Arai Station opens.
• 196110 December: Minami-Takada Station opens.
• 196624 August: the Nagano–Naoetsu section, including this line, is electrified at 1,500 V DC.
• 19691 October: Taguchi Station is renamed Myōkō-Kōgen.
• 197818 May: a debris flow from the Shiratagiri River damages the Myōkō-Kōgen–Sekiyama section; the line reopens on 6 September after a truss bridge made for the Ōfunato Line is reused as a new Shiratagiri River bridge.
• 19871 April: with the breakup and privatisation of Japanese National Railways, the Shin'etsu Main Line, including this section, passes to JR East.
• 201419 October: a new alignment around Wakinoda enters service and the station is relocated about 120 m west, beside the future Shinkansen station.
• 201514 March: with the Hokuriku Shinkansen extended to Kanazawa, the Naoetsu–Myōkōkōgen section is transferred from JR East to Echigo TOKImeki Railway and renamed the Myōkō Haneuma Line; Wakinoda Station is renamed Jōetsumyōkō.
• 201623 April: the sightseeing train "Echigo TOKImeki Resort Setsugekka" begins operating.
• 20177 April: operational control is separated from JR and merged with that of the Nihonkai Hisui Line.
• 202614 March: Myōkō-Kōgen Station begins accepting the Suica IC card, usable there only on the connecting Kita-Shinano Line.