its proposal was initially discussed in 1930's
it was abandoned in 1943 for the 2nd World War.....
Yes, maglev trains can be built underground. In fact, the majority of the Chuo Shinkansen maglev line being built in Japan will be underground.
Shinkansen was created in 1964.
The first Shinkansen came out in 1964.
Tōkaidō Shinkansen was created in 1964.
Nagano Shinkansen was created in 1997.
Tōhoku Shinkansen was created in 1982.
Jōetsu Shinkansen was created in 1982.
Shinkansen Recordings was created in 1996.
Kyushu Shinkansen was created in 2004.
Shinkansen Relay was created in 1982.
Sanyō Shinkansen was created in 1972.
Shinkansen is used both as a singular and a plural in Japanese.