John C. Frémont's major government exploring expeditions of 1843-44 and 1845 crossed the Basin by both Smith's and Walker's routes. The Unknown, Mary's, or Ogden's River was renamed by Frémont for the famous German geographer and naturalist Alexander von Humboldt. It was Frémont too who coined the term "Great Basin" and helped imbed the reality of the drainage and physiography in the public consciousness. Meanwhile, the Humboldt River, often crossable without even a wet boot, was becoming the route of choice for the 49ers and the "highway of the West."
Though emigration slowed, the transit corridor became more important. In 1868-69 the Central Pacific crews raced across the Basin to meet the Union Pacific at Promontory, Utah. U.S. Highway 40 followed from the 1920s to the 1950s and after the 1960s Interstate 80 made only minor adjustments in the route. Many of the railroad towns, established to provide water in the steam era, became regional supply places for area ranching and mining. The freeway's bypass system strengthened some towns, dried up the lifeblood traffic of others, and physically obliterated a few of these basin oasis towns. Route doglegs that may at first seem odd and out of the way remain the most cost-effective connection between points, as they utilize the low passes between ranges and the meandering route of the Humboldt River.