Hokuhoku Line

The Hokuhoku Line (ほくほく線) is a Japanese railway line in Niigata Prefecture that runs from Muikamachi in Minamiuonuma City to Saigata in Jōetsu City. It is the sole railway line operated by Hokuetsu Express (北越急行). Construction of the line first began in 1968 by the Japanese National Railways (JNR), and was initially referred to as the Hokuetsu-Kita Line (北越北線). However, the construction of the line was plagued by numerous delays, and was finally completed as a third sector line on 22 March 1997, including the 10,472 m Akakura Tunnel, the longest on a non-JR line.

Unlike most other third sector company lines, the Hokuhoku Line made steady profits after its opening, as the former Hakutaka Limited Express train service, which travelled using the line, served as the principal link between the Tokyo metropolitan area and the Hokuriku region until the opening of the Hokuriku Shinkansen in 2015. The line's former maximum speed limit of 160 km/h allowed the Hakutaka to become the fastest narrow gauge train service in the country, matched only by the standard gauge Keisei Skyliner services to Narita International Airport as the fastest non-Shinkansen service (also at 160 km/h); however, following the withdrawal of Hakutaka services on the line on 14 March 2015, the maximum speed limit of the line was reduced to 130 km/h.

Services
Originally, the line acted as a connecting route to the Jōetsu Shinkansen at Echigo-Yuzawa Station. Upon the opening of the Hokuriku Shinkansen on 14 March 2015, the limited express services Hakutaka of the line, which had run from 1997 with an average daily ridership of 6,900 passengers, were withdrawn. Since then, a daily special rapid service Snow Rabbit has been served, instead of Hakutaka, until 18 March 2023, where all rapid service has been discontinued.

Trains from Muikamachi are described as down-bound, whereas those from Saigata are described as up-bound.

Local Service
17 return trips are operating each day, with additional 1 service operating on weekends and holidays. Two return trips running on Sundays are designated as Yumezora, in which movies will be played on the ceiling of the train when the trains are going through a tunnel. Since the discontinuation of Hakutaka in 2015, required trip time is reduced by 10 minutes. Through-trains to and from JR Lines do not stop at some stations of the Jōetsu Line and Shin'etsu Main Line.

Chō-Slow Service - Snow Turtle (スノータートル)
Snow Turtle is a special service with irregular schedules and available for rental by organizations. Being a comical counterpart of Snow Rabbit, the trains run at a very low speed, as slow as 10 km/h, to give passengers a chance to experience winds while opening the side doors of the trains. Meals are also provided during the four-hour journey.

Rapid Service
Two down-bound and three up-bound trains are operating each day between Echigo-Yuzawa and Naoetsu.

Chō-Rapid Service - Snow Rabbit (スノーラビット)
Two down-bound and one up-bound trains are operating each day, and one of the down-bound train runs through to Arai of the Myōkōhaneuma Line. The fastest service, which stops only at Tōkamachi, only takes 57 minutes travelling from Echigo-Yuzawa to Naoetsu.

Passing loops
There are three passing loops on the Hokuhoku Line. Each has one bi-directional through track to allow full line speed. However, the passing loops has been abandoned since the discontinuation of Hakutaka service.

Akakura
Between Uonumakyūryō and Misashima in Tōkamachi, Niigata. It is in the 10472m Akakura tunnel.

Yakushitōge
Between Tōkamachi and Matsudai in Tōkamachi, Niigata. It is in the 6199m Yakushitōge tunnel.

Gimyō
Between Matsudai and Hokuhoku-Ōshima in Tōkamachi, Niigata. It is in the 9130 m Nabetachiyama tunnel(ja:鍋立山トンネル).

Rolling Stock
10 HK100-0 series single-car units were built by Niigata Transys for use on local, rapid and Chō-Rapid Snow Rabbit trains between Echigo-Yuzawa and Naoetsu, and started operation since its opening in 1997. Having a maximum speed of 110 km/h operating on the 160 km/h lines, these trains feature a fast acceleration of 3.0 km/h/s to minimize disruptions of Hakutaka train services. 1 permanent 2-car set known as HK100-100 series entered service in 2003 for the Yumezora video projection and event train together with 2 units of HK100-0 refurbished in 2008 named Yumezora II.
 * 12 HK100 series

Former
18 cars of 681-2000 series and 9 cars of 683-8000 series trains, nicknamed Snow Rabbit Express (SRE) were built by Kawasaki Heavy Industries, with final assembly at Niigata Transys for operation on the Hakutaka limited express trains between Echigo-Yuzawa and Kanazawa stations. At a operating speed of 160 km/h, this was the fastest train in the country to run on narrow gauge. Following the retirement of the Hakutaka services, the trains were transferred to JR West for operation on Shirasagi limited express services.
 * 681-2000 series - Hakutaka
 * 683-8000 series - Hakutaka

Stations
The Hokuhoku line is entirely in Niigata Prefecture.
 * Service patterns:
 * ● All trains stop
 * ○ Some trains stop
 * ｜ All trains pass
 * ＊ Seasonal stop
 * Track:
 * ∥: Double-track section
 * ∧: Double-track section begins
 * ∨: Double-track section ends
 * ｜: Single-track section
 * ◇: Passing loop