In 1839, he became the colleague of Agassiz as professor of history and physical geography at the College of Neuchâtel (a.k.a. Neuchâtel Academy). When the institution got suspended in 1848, Guyot travelled to the United States, where he settled in Cambridge, Massachusetts. He delivered lectures for a course at the Lowell Institute which were later published as "Earth and Man" (Boston 1849). For several years the Massachusetts Board of Education employed him as a lecturer on geography and methods of instruction to the normal schools and teachers' institutes.