It’s impossible to separate the history of the United States from the history of its post office. After all, Benjamin Franklin was appointed the nation’s first postmaster general all the way back in 1775, after his fellow colonists rebelled against Britain’s Royal Mail and established the Post Office Department, the forerunner of the United States Postal Service (USPS).

Ever since, the post office has made it its mission to deliver the mail to all Americans, reaching ever further and faster to keep pace with the growing nation. From horse-drawn carriage to railroad to pneumatic tube, here’s a brief history of how the post office has delivered the mail over nearly two and a half centuries.

Post riders, the earliest postal carriers in American history, traveled along a system of post roads that the Constitution authorized the federal government to create. The roads connected small post offices, where people would wait in long lines to collect their mail. By 1789, 75 Post Offices and about 2,400 miles of post roads served a population of almost 4 million.

By the late 1700s, stagecoaches (large horse-drawn vehicles) had begun to replace individual post riders on the roads. At the urging of Congress, the post office granted contracts to stagecoach lines to help link Eastern communities with the expanding frontier. The Gold Rush opened the floodgates of Westward migration in the 1850s, and stagecoaches carried mail along new overland routes stretching all the way to California.

In 1813, six years after Robert Fulton launched the first viable commercial steamboat line in New York, Congress authorized the postmaster general to contract with steamboat companies to transport the mail. By the late 1820s, steamboats were ferrying mail up and down the East Coast and along the Mississippi River. Beginning in December 1848, U.S. Mail traveled by steamship to California via the Isthmus of Panama, a journey that took roughly three weeks.

Those looking for a speedier delivery could, for a short time, at least, turn to the Pony Express, a private service that began running between St. Joseph, Missouri and California in April 1860. Riders rode specially selected horses an average of 75 to 100 miles daily, changing horses at relay stations set at 10-15 mile intervals along the nearly 2,000-mile route; the trip took about 10 days, about half of the time of the regular overland mail. The post office contracted with the Pony Express for only a few months before the service shut down in October 1861, shortly after the completion of the transcontinental telegraph line.

Though the post office first transported mail via the “iron horse” in 1832, its use of the railroad entered a new era of efficiency after the Civil War, with the completion of the nation’s first transcontinental railroad. From the 1860s to the 1970s, clerks would sort and distribute mail on trains crisscrossing the country; at its height in the mid-20th century, the Railway Mail Service (RMS) would handle 93 percent of all non-local mail in the United States.

In 1899, an electric automobile collected the mail from 40 mailboxes in Buffalo, New York in an hour and a half—less than half the time of a horse-drawn wagon. The use of automobiles (both electric and gas-powered) increased after 1913 when postal carriers began delivering packages as well as letters, and by 1933 only 2 percent of urban postal vehicles were horse-drawn. With the growth of the suburbs in the 1950s, city routes were motorized for the first time, with Jeeps, sit-stand trucks and small vehicles known as “mailsters” among the earliest delivery vehicles.

The post office’s introduction of Rural Free Delivery (home delivery to rural addresses, not just urban ones) in the early 1900s spurred the increased use of motorized vehicles, and postal carriers also experimented with motorcycles as soon as they became commercially available. The use of motorcycles to deliver mail peaked in the 1920s; after that, they were replaced with four-wheel automobiles and trucks with more space to hold letters and packages.

The first authorized U.S. Mail flight took place in 1911 when aviator Earle Ovington piloted his Bleriot monoplane between Garden City and Mineola, New York. In 1918, scheduled Airmail service launched, using pilots and planes borrowed from the Army. Charles Lindbergh flew the mail between Chicago and St. Louis in 1926, a year before he made his historic nonstop flight across the Atlantic. In 1924, transcontinental airmail took one day, 10 hours and 20 minutes, compared to the six to seven hours it might take today.

During World War II, the post office helped Americans stay connected to their loved ones fighting abroad (without transporting tons of letters via airmail) with Victory Mail or V-Mail, based on a technique originally developed by Eastman Kodak to process bank records. Written on special lightweight stationery that folded into its own envelope, letters from the United States were opened and microfilmed.

The rolls of film were shipped to military stations abroad, where they were developed, after which printed copies of the letters were delivered to soldiers. For soldiers’ letters home, the process was reversed. In 1944, a fact sheet from the Office of War Information claimed that V-Mail had saved some 4,964,286 cargo pounds since it launched in mid-1942.

In the early 20th century, underground systems of pneumatic tubes linked postal facilities within each of six U.S. cities. Canisters packed with up to 500 letters were placed into the tubes and propelled by pressurized air between postal facilities at a speed of 30 mph. Suspended in 1918 amid the rise of more efficient automobiles, the pneumatic tube system was revived in the 1920s in New York City and Boston, but retired for good in the early 1950s, ending one of the most unconventional of the many methods the post office has used to deliver the mail.