An Ohio woman was shocked by a “return to sender” letter that she first dropped in a mailbox almost three decades ago.

Kelli Butts said she was surprised to see a letter in her South Vienna mailbox recently from a woman who bought her home almost 20 years ago.

Inside the envelope was a second envelope, Butts said, and an old stamp caught her eye.

“Then I looked at the postmark and it was from 1987,” she said.

The letter was a card Butts had mailed to a friend across the state almost three decades ago. Just a “hello” to catch up, Butts said, in the days before text messages and emails.

Two homes and almost three decades later, she was surprised by the decades-old card, never opened, back in her mailbox with a “return to sender” marking. The woman who now lives in the home it was returned to was kind enough to forward it to Butts’ current address.

“I thought it was very neat that she took the time to look me up, two different moves,” she said.

She reached out with the simple question of: Where could the letter have been all these years?

“How it got back in our mail stream we can’t really determine exactly,” David VanAllen with the United States Postal Service said.

The letter in recent weeks reappeared in the mail system, he said, and a carrier attempted to deliver it to the Zanesville address. But that home not longer exists, so it was returned to Clark County.

More than 350,000 pieces of mail are processed each minute by the United States Postal Service, according to federal data.

USPS processes and delivers more than 509 million pieces of mail every day, totaling more than 154 billion in 2015.

“At this point my best guess is someone found it somewhere recently and put it back in a mailbox,” VanAllen said.

But these kinds of stories do pop up, he said, where mail shows up years after it was first sent.

New technology with tracking numbers helps the USPS keep track of more and more packages and pieces of mail each year, VanAllen, but not all letters get a tracking number.

The letter lost and now returned has not allowed Butts to lose her faith in the U.S. mail system, and she said she plans to send a thank-you card to the woman who forwarded her the letter.