A series of tiny doors scattered through the alleyways of an Australian city has left people scratching their heads.

Tourists and locals have been sharing videos after stumbling across an array of “fairy doors” in Brisbane – prompting many to ask: “Why are they here?”

The first “mysterious” mini doorway, which measures just a few inches in height, appeared in Burnett Lane in the city’s CBD back in 2017.

Since then, more have been steadily popping up, with an array of “weird and wonderful” tiny doors now dotted around for people to find and enjoy.

The miniature attractions are the brainchild of artist Mace Robertson, who recently admitted there are so many doors, he cannot remember how many he has installed.

Robertson said he’d been inspired to create the series after spotting the global “fairy doors” phenomenon, a so-called “magical portal between” our world and the fairy realm usually found at the base of a tree trunk overseas.

“I saw them pop up in other cities around the world and I thought Brisbane needs more art and why not do that,” he told the Brisbane Times in March.

His first creation was a red door, complete with a window archway and even the number “45a”, but there have been an array of different designs in the years since – and finding them all has become a popular sport.

Social media is awash with videos from visitors and locals alike as they stumble across the doors before attempting to find more.

Food blogger Adrian Widjy recently shared his experience with Brisbane’s mini doors, declaring it the “best thing” he’d discovered about the Queensland city.

“Have you heard or seen these #TinyDoors or #FairyDoors around Brisbane?” he asked his 262,000 followers.

“It is such a fun activity hunting them down given that there are plenty around Brisbane City,” he said. “They have amazing details!”

His video shows three different designs he located in Fortitude Valley, including a fire station with doors.

Some even open to reveal a QR code, which plays a behind-the-scenes film with the artist who created them.

The Sydneysider then uncovered three more in Fish Lane, South Brisbane, including one he described as having a “medieval theme”.

Adrian also marveled over a “mini retro music store” – stating the artwork was “unreal”.

“It even had a ‘back in 5 minutes’ sign,” he said.

The content creator isn’t the only person to have created a TikTok video about the tiny doors, with one social media user sharing a video of himself knocking on Robertson’s original piece.

“POV: You find Ratatouille’s house,” he captioned the video.

Another user said they spent “7 hours on an adventure” locating as many installations as possible.

“That is so cool,” one delighted user wrote.

“It’s a door able,” someone else laughed.

As one local admitted: “Lived in Brisbane my entire life and had no idea.”

“I had no idea about these! And I live here,” another agreed.

“I didn’t know this existed,” one mused.

Others said their kids loved the local attraction, revealing they often leave notes for the “fairies” to find at their doors.