1861: Library of Congress: The first transcontinental telegraph system was completed by Western Union, making it possible to transmit messages rapidly (by mid-nineteenth-century standards) from coast to coast. This technological advance, pioneered by inventor Samuel F. B. Morse, heralded the end of the Pony Express. Only two days later, on October 26, the horseback mail service that had previously provided the fastest means of communication between the eastern and western United States officially closed. The short-lived Pony Express had been established only one and one-half years earlier, in April 1860. The nearly 2,000-mile route - running through present-day Kansas, Nebraska, the northeast corner of Colorado, Wyoming, Utah, Nevada, and California - included vast stretches of rugged terrain once thought impassable in winter.