Question: Who came up with the idea to build the transcontinental railroad?
Disambiguated questions and answers: question: Who came up with the idea to build the transcontinental railroad and presented a plan to congress?
Who came up with the idea to build the transcontinental railroad and did much of the land survey work for determining the best route over the Sierra Nevada?
answer: Asa Whitney
Whitney
Theodore Dehone Judah
Theodore Judah
Natural Questions answer: Dr. Hartwell Carver (from the Wikipedia article "First Transcontinental Railroad")