Theodore Dehone Judah (March 4, 1826 – November 2, 1863) was an American railroad and civil
engineer who was a central figure in the original promotion, establishment, and design of the
first Transcontinental Railroad. He found investors for what became the
Central Pacific Railroad (CPRR). As chief engineer, he performed much of the land
survey work to determine the best route for the railroad over the
Sierra Nevada mountains.