The Pony Express is a legendary service ... that only lasted for 18 months.The first mail delivered via the Pony Express was sent on April 3, 1860 when it left St. Joseph, Missouri. Near midnight on April 14, 1860, the mail reached its destination in San Francisco. It was 155 years ago, but that first journey remains memorable today, even though the service only operated until October 1861 closing just 81 weeks after...