The idea of a transcontinental railroad caught fire in the late 1840s, when New York merchant Asa Whitney presented a plan to Congress.

Then Whitney published a pamphlet explaining the idea to the public and the idea took hold.

The government sent engineers out west to evaluate five proposed routes for the railroad.

They determined that, while each route posed its own set of challenges, any of them could work.

And the debate began.

Get full access to Photo of the Day at look.substack.com/subscribe