The Tōbu Keishi Line (東武啓志線, Tōbu Keishi-sen) was a 6.3 km freight railway line operated by Tobu Railway, which ran from Kami-Itabashi Station on the Tōbu Tōjō Line, initially to a Japanese Army arsenal depot in modern-day Hikarigaoka. Following the arrival of US military forces immediately after World War 2, the area was converted to the Grant Heights housing complex (in present-day Hikarigaoka in Tokyo, Japan). The line was named in 1946 after Hugh Boyd Casey, the project engineer for Grant Heights.