how is this system remembered?
In 1869, the United States Post Office issued the first U.S. postage stamp to depict an actual historic event, and the subject chosen was the Pony Express. The National Pony Express Association is a nonprofit, volunteer-led historical organization. Its purpose is to preserve the original Pony Express trail and to continue the memory and importance of Pony Express
Pony Express
In 1869, the United States Post Office issued the first U.S. postage stamp to depict an actual historic event, and the subject chosen was the Pony Express. 
where did the first pony express mail delivery take place UNANSWERABLE what is it? It was a mail service delivering messages, newspapers, and mail using relays of horse-mounted riders how is it operated? In 1860, the roughly 186 Pony Express stations were about apart along the Pony Express route. At each station stop, the express rider would change to a fresh horse, taking only the mail pouch called a "mochila" (from the Spanish for pouch or backpack) with him.  In emergencies, a given rider might ride two stages back to back, over 20 hours on a quickly moving horse. when did they start it? April 3, 1860 which are some of the main stations? Platte Bridge Station where is it located? Wyoming can you mention the names of a few riders of the mail delivery system? Johnny Fry , Billy Richardson who was the former? He was the first "official" westbound rider of the Pony Express. when did they stop it's operations? The Pony Express announced its closure on October 26, 1861 had they faced any attack during the mail delivery? The Paiute War was a minor series of raids and ambushes initiated by American expansion into the territory of the Paiute Indian tribe in Nevada, which resulted in the disruption of mail services of the Pony Express. what type of horses were used for this? California horses, native ponies,  Morgans, Mustangs what are the features of the last one? UNANSWERABLE
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Pony Express [SEP] Commemorations
In 1869, the United States Post Office issued the first U.S. postage stamp to depict an actual historic event, and the subject chosen was the Pony Express. Until then, only the faces of George Washington, Benjamin Franklin, Thomas Jefferson, and Andrew Jackson were found on the face of U.S. postage. Sometimes mistaken for an actual stamp used by the Pony Express, the "Pony Express Stamp" issue was released in 1869 (8 years after the Pony Express service had ended) to honor the men who rode the long and sometimes dangerous journeys and to commemorate the service they provided for the nation.