Minamiaso Railway Takamori Line

The Takamori Line (高森線) is a Japanese railway line in Kumamoto Prefecture, between Tateno Station, Minamiaso, and Takamori Station, Takamori. This is the only railway line Minamiaso Railway (南阿蘇鉄道) operates. The line traverses the southern part of Mount Aso caldera.

History
The single-track line was opened by the Japanese Government Railways in 1928. The only passing loop is at Nakamatsu. Freight services ceased in 1984. The third-sector company took over the former JNR line in 1986. The MLIT tested a DMV railbus on the line in November, 2007. The line is not electrified. It uses a simplified automatic railway signalling system.

Uncompleted extension
After the Takachiho line opened in 1972, construction of the 23 km section to Takamori continued until 1975 when flooding in the 6500 m Takamori tunnel (7 km north of Takamori) resulted in work being suspended. Construction was formally abandoned in 1980.

Stations
All stations are within Kumamoto Prefecture.

† The station name of Aso-Shimodajō has changed three times:
 * 12 February 1928: Aso-Shimoda (阿蘇下田)
 * 1 August 1993: Aso-Shimodajō-Fureai-Onsen (阿蘇下田城ふれあい温泉)
 * July 15 2023: Aso-Shimodajō (阿蘇下田城)

With 22 kana, Minamiaso Mizu-no-Umareru-Sato Hakusui-Kōgen Station (南阿蘇水の生まれる里白水高原駅|南阿蘇水の生まれる里白水高原]) was tied with Chōjagahamashiosaihamanasukōenmae Station in Ibaraki Prefecture as the longest station name in Japan, however since 2020, the record is held by Tōjiin Ritsumeikan University Station in Kyoto, with 26 kana.

Earthquake closure and reopening
The entire Takamori Line was closed following significant damage to track and infrastructure following the Kumamoto earthquakes in April 2016. A section of the line between Nakamatsu and Takamori resumed service in July of the same year.

However, the section between Tateno and Nakamatsu could not be reopened because of extensive earthquake damage to the track. The Ministry of Land, Infrastructure, Transport and Tourism estimated that a complete restoration would cost between 6.5 to 7 billion yen. After work was completed to restore the railway, the full line re-opened on 15 July 2023. Major work to reopen the line included the complete rebuilding of the badly damaged No. 1 Shirakawa arch bridge.