Whether it is because certain items require added protection, to add to the unboxing experience or a combination of both, custom cardboard boxes have become more desirable and necessary amongst businesses than ever before.

There is a long and fairly exhaustive list of items that are either restricted or banned outright from being sent through the post and a lot of rules surrounding the costs of particular types of deliveries.

A lot of the time, these rules and sophisticated boxes both emerge as the result of tests to the established system. With that in mind, here are some of the most unusual items ever to go through the postal service.

An Entire Building

For as long as parcel post has existed, people have been pushing its capabilities to their absolute limits, but a step too far was the astonishing tale of a bank in Utah that was posted brick by brick via parcel post.

In 1916, William Horace Coltharp faced a dilemma; he had been instructed to construct the first bank in the relatively small settlement of Vernal, Utah, but getting the shipment of bricks he wanted would have cost over £50,000 adjusted for inflation.

To get around this, Mr Coltharp exploited a loophole in the US Postal Service at the time that shipping cost was only measured by distance as long as parcels did not exceed the maximum shipping weight of 50 lbs.

What Mr Coltharp did was ship the bricks in over 1500 parcel crates in packs of ten, appropriately stamped of course, and by the time the loophole was fixed the whole building had made it to the construction site at great cost to the USPS.

To this day, the bank is still nicknamed the Parcel Post Bank to celebrate its rather ignoble origins.

A Sick Cat

Animals cannot be sent through the postal service for what one would hope to be fairly obvious reasons. Whilst there have been dedicated cardboard boxes with air holes for carrying animals around, they are usually meant as temporary transportation for families relocating with their pets.

However, in 1897, a cat was not only posted to a veterinarian, they were launched, wrapped in a cotton sack enclosed within a tube canister, through a pneumatic tube in New York City.

It was sent after a set of fine china, a pot of hot tea and some eggs were sent through to prove how effective the system was for sending fragile objects safely.

The cat emerged unharmed, although it did attempt to run away once the tube was opened having understandably felt a terrible fright from the sudden journey. Eventually, they were bundled into a basket and taken to the vet to be taken care of.

The pneumatic tube system has long since been shut down outside of a few heritage and localised applications, but the story of the cat in the tube has gone down in history alongside the stories of children travelling via the postal service until both were understandably banned.

The Most Expensive Diamond In History

One of the most valuable pieces of jewellery ever made currently takes pride of place at the Smithsonian Institution and has done so since 1958. However, the path it took to get there is one of the most remarkable achievements of the parcel post service.

On the suggestion of George Switzer, then-owner Harry Winston was persuaded to donate the Hope Diamond to the National Museum of Natural History as part of a gem collection they aimed to begin.

Whilst reluctant, particularly given the reputation the Hope Diamond had of being cursed, he ultimately agreed, but the question became not about if the diamond would be delivered but how. 

Ultimately, Mr Winston did not opt for some kind of grand secure delivery but instead posted it through registered delivery at a cost of around £2, with an additional £140 spent on insuring the diamond for $1m.

Marked “fragile”, the diamond was placed in a box wrapped in typical brown parcel paper and was sent from New York to Washington DC by train, was handed to postal carrier James Todd, who promptly drove the impossibly valuable parcel to the Museum, where it was signed by Secretary for the Smithsonian Leonard Carmichael.

Remarkably, it was Mr Winston’s idea to send the diamond through the conventional postal service, claiming that it was the “safest way” to send rare gems, in no small part because there is safety in numbers and no expectation from jewellery thieves that something so rare will use the same parcel post as any other mail order goods.