A Virginia woman who has spent more than a year digging a tunnel under her home and documenting the project on TikTok was recently stopped by officials in her town after the popularity of her account brought their attention to her project.

Spending hours heaving dirt and rocks from the ground might seem like an unusual pastime, but it has a history: hobby tunnelists of yore include the Fifth Duke of Portland, who in the 19th century built an underground ballroom on his property, and, more recently, the so-called mole man of London, who spent 40 years making tunnels before he was discovered.

Here’s a look at their underground activities, and what happened after they were brought to light.

A TikTok Tunneler

Since 2022, the TikTok creator @engineer.everything has been documenting her attempt to build an emergency shelter under her home.

The tunneler, known as “Tunnel Girl” by some fans online, said in a phone interview this month that her tunnel had a 30-foot entrance and a main chamber 22 feet below ground. She spoke on the condition that she be identified by her online nickname, Kala, because of privacy concerns.

She said that she started the project because she wanted to do something that was “technically challenging and would require me to learn a lot of new skills.”

She was not prepared for how much attention the project would receive online. “I was hoping to share with kind of a smallish group of people who are interested in the engineering and technical challenges of it, and I really did not intend for it to go mainstream,” she said.

Kala’s work came to a halt in December, when the town she lives in, Herndon, Va., issued a stop work order. She said that she has since submitted permit applications and blueprints to the town and is waiting to hear back.

In a statement, the town of Herndon said a site inspection took place on Dec. 7, a few weeks after a round of media attention that included a Bloomberg opinion piece and an NBC article about the tunnel. “The town is working with the property owner to correct any violations and ensure that the property is safe and in compliance with the code,” the statement said.

But Kala is far from the first person to capture the attention of the world with an off-the-books tunnel project.

A Canadian Mystery

There was an international media frenzy in 2015 when a tunnel over 33 feet long was found in the north of Toronto with tools, empty bottles and food containers inside. The Toronto police investigated the tunnel for more than a month but were unable to find answers and asked the public for help. Speculation about drug labs and terror plots followed, but the explanation ultimately involved nothing illicit.

A little over a week after the police asked for information, the digger confessed in an interview with The Toronto Sun. Elton McDonald, a 22-year-old construction worker from a neighborhood near the tunnel, said he had built it. “It was just something I always wanted to do,” he said.

The tunnel was quickly filled in. It was located on property owned by Toronto and Region Conservation Authority but under a management agreement with the city of Toronto, which maintains the property on behalf of the conservation authority.

The conservation authority, a nonprofit organization responsible for conserving and managing more than 1,338 square miles (3,467 square kilometers) of land and water resources in the area, said in a statement that the Toronto police “took the necessary steps to fill in the tunnel.” The nonprofit “was not involved in this process,” it said.

A State Landmark

Not every local authority races to fill in a tunnel when it’s found.

After Baldassare Forestiere arrived in the United States from Sicily in the early 1900s, he constructed an expansive complex of underground rooms and gardens at his home in Fresno, Calif.

Mr. Forestiere created each room as he worked without written plans, according to the website for the complex, Forestiere Underground Gardens, which is now a tourist attraction. Mr. Forestiere dug for 40 years and planted orange, lemon and grapefruit trees in his underground network.

His hobby was celebrated by the state of California, which registered the complex as a historical landmark in 1978, calling it a monument “to a creative and individualistic spirit unbounded by conventionality.”

A London Mole Man

An East London man the British press called “the Mole Man of Hackney” spent 40 years digging a tunnel network under his house before the local government obtained a court order in 2006 to stop the digging and to fill the holes with cement, according to the Guardian.

William Lyttle, who died in 2010 after being evicted from the home, told the Guardian that he had first tried to dig a wine cellar, then kept going. “Tunneling is something that should be talked about without panicking,” he said.

An Eccentric Entomologist

In September 1924, a truck sank into the ground near Dupont Circle in Washington, revealing tunnels created by Harrison G. Dyar, an entomologist.

Dr. Dyar said that he had started digging the tunnels in 1905 or 1906, prompting The New York Times to declare “Moth Lover Dug Tunnels.”

“I did it for exercise,” Dr. Dyar said at the time. “Digging tunnels after work is my hobby. There’s really nothing mysterious about it.”

Dr. Dyar dug the tunnels when he was the honorary custodian of Lepidoptera, or moths and butterflies, at the United States National Museum (now known as the National Museum of Natural History). He also had two families who lived in separate homes — each of which had tunnels. Contrary to urban legend, the two sets of tunnels weren’t connected, said Marc Epstein, an entomologist and the author of the book “Moths, myths, and mosquitoes: the eccentric life of Harrison G. Dyar, Jr.”

In the decades since the delivery truck discovery, one set of the tunnels has been blocked, and the other was demolished during construction, Dr. Epstein said.

A Burrowing Duke

In the 1800s, William John Cavendish Scott Bentinck, the Fifth Duke of Portland, built 2.75 miles of tunnels and an underground ballroom on his property, Welbeck Abbey, near Sheffield in England, according to an exhibit at the Harley Gallery on the Welbeck Estate.

He was known as the “burrowing duke,” and rumors circulated that he had other unusual habits, including always wearing three pairs of socks, only eating roast chicken, and communicating exclusively by letter through his bedroom door, according to the exhibit.

Today, the tunnels are not open to visitors. A representative for the Welbeck Estate did not respond to questions about their current status.