Since the 1930s, a peculiar postal tradition has persisted in the heart of the Grand Canyon: mail delivery by mule. In Supai, Arizona, the only way to get your letters and parcels is via a trusty mule train, the last of its kind in the United States. This endearing operation sees between 10 and 22 mules, led by a lone wrangler on horseback, making the arduous nine-mile journey to the Supai Post Office five days a week.

The trek is no quick jaunt. It takes about three hours to descend into the canyon and five hours to climb back up. Each mule, a steadfast courier of the canyon, carries up to 200 pounds of mail and goods, balanced carefully for stability. Once the deliveries are made, the wrangler untethers the mules, who then follow the trail back on their own, like seasoned postal workers clocking out after a long shift.

The Supai Post Office, nestled at the canyon's base, offers a unique "Mule Train" postmark, a testament to this extraordinary journey. Recognized by Condé Nast Traveler as one of the world's most unusual postal locations, this route has been a lifeline for the Havasupai community for decades, connecting them to the outside world in a way that no helicopter or road ever could.

In a world increasingly dominated by drones and digital communication, the mule mail route to Supai stands as a charming relic of the past, reminding us that sometimes, the old ways are the most enduring. So, next time you send a letter, remember the mules of Supai, trotting through the canyon, carrying a piece of history on their backs.