Tenryū Hamanako Line

The Tenryū Hamanako Line (天竜浜名湖線), or Tenhama Line (天浜線) for short, is a Japanese railway line in Shizuoka Prefecture, paralleling the north coast of Lake Hamana between Kakegawa Station in Kakegawa and Shinjohara Station in Kosai. This is the only railway line of Tenryū Hamanako Railroad (天竜浜名湖鉄道).

History
The Japanese National Railways Futamata Line (二俣線) was built as an alternative route for the Tokaido Main Line and in particular as a backup for the bridge over Lake Hamana, which was considered potentially vulnerable to weather disruption. The Japanese military also supported the project as the new line would be less vulnerable to coastal attack than the existing section of the Tokaido Main Line. Operations began on April 17, 1935, between Kakegawa and Enshū-Mori. Construction work progressed in the opposite direction with the Futamata-Nishi Line (二俣線西) connecting Shinjohara with Mikkabi on December 1, 1936. This line was extended to Kaminobe by April 1, 1938, and the two lines were connected on June 1, 1940.

The line was used as a detour for the Tokaido Main Line following damage to it caused by the Tōnankai earthquake in December 1944 and military actions in July 1945.

Steam locomotives ceased service on the line in 1971, and all scheduled freight services were discontinued from 1984.

Operations of the former Futamata Line were taken over by the third sector company Tenryū Hamanako Railroad in 1987, the same year Japanese National Railways was privatized.

Thirty-six features of the line (including bridges and station buildings) are registered tangible cultural properties of Japan.

Former connecting lines

 * Tenryu-Futamata station – Construction started on a 35 km line to Chubu-Tenryu on the Iida Line in 1967. Proposed to involve 20 bridges and 14 tunnels, about 13 km of roadbed, and about 50% of the overall work had been completed when construction was abandoned in 1980.
 * Kanasashi station – The 26 km 762mm gauge line from Entetsu Hamamatsu station on the Enshu Railway Line to Okuyama opened between 1914 and 1923. The 8 km Entetsu Hamamatsu - Hikuma section was electrified at 600 VDC in 1950, the line closing in 1963/4.

Description

 * Track: Single
 * Power: Internal Combustion (Diesel)
 * Railway signalling: Simplified automatic