(NEXSTAR) – Were you expecting a package that never arrived? A present, maybe? A birthday card? Or perhaps a care package from your Aunt Linda with some crisp new socks inside?

If it was shipped via the United States Postal Service, chances are it’s in Atlanta. Or at least it was, at some point.

There are several reasons that the U.S. Postal Service might fail to deliver a package or piece of mail to its intended recipient in a timely manner: e.g., the sender may have provided the wrong address (or an illegible one), or maybe the item was shipped with insufficient postage. It’s also possible the contents of the package somehow came loose in the mail, making it tough to determine where they came from. In these cases, USPS workers try to return those packages or items right back to the sender.

But when that’s not immediately possible (usually because there’s no return address), those items get shipped off to USPS’ consolidated Mail Recovery Center in Atlanta.

The Mail Recovery Center, formerly known as the Dead Letter Office, is not where packages immediately go to die or be disposed of, despite the facility’s former name. Rather, the Mail Recovery Center (MRC)’s first objective is to determine the identity and location of the senders or recipients by having its investigators examine, scan, or ultimately open the lost mail and packages.

If the investigators at the MRC find a name or a clue associated with an address, great. The package can be shipped off to the recipient, or back to the sender.

If not — and if the contents of the package are determined to be valued at $25 or more (or $20 or more in cash) — they stay right where they are in Atlanta.

The MRC holds these types packages (if they meet all other guidelines) for at least 30 days, or 60 days for barcoded or “intelligent” mail. During this time, the sender or recipient is offered the opportunity to request help online, and later file a Missing Mail Search Request with as much descriptive information as possible, along with any photos.

“If we are still unable to match the shipment to a recipient, these items are handled in a variety of ways per regulatory policies and shipper instructions,” a USPS representative for tells Nexstar.

The USPS rep could not provide specific details, though the department’s site indicates that unclaimed items could be trashed, recycled, or donated to “charitable or welfare organizations.” (For a while, after the turn of the 20th Century, some of the strangest unclaimed items — or “curiosities” — were also sent to the Smithsonian Institution, per a Smithsonian article cited by a USPS representative.)

In other cases, these lost or unclaimed items are put up for auction and sold off to the highest bidder by a government-contracted agency. GovDeals.com, for instance, currently has books, apparel and large lots of “general merchandise” from Atlanta up for bid online.

Of course, senders can easily take steps prevent their packages from becoming lost forever, according to the USPS. For starters, the agency recommends covering up any older markings on boxes used to send packages, and using sturdy tape to make sure parcels stay intact. Senders are also urged to provide accurate, legible addresses on the package (both for the recipient and the themselves), and also include those addresses on a slip of paper and place it alongside the package’s contents.

“When sending a package, follow these guidelines to get shipments off to a good start,” reads an official USPS webpage. “Safe delivery starts with careful preparation,” the site adds.

Otherwise, its quite possible someone else — an online bidder, perhaps — could be opening your lost birthday presents, or enjoying the crisp new socks that Aunt Linda intended for your feet. And that would just break her heart.