Watching your own head on a plate or posing for a photo while strolling on the ceiling just are two of the surreal pictures given up by a Croatian museum that has spread worldwide.

"It's unusual, it forces you to use your brain, but it's also entertaining," says Roko Zivkovic, who created the first Museum of Illusions in Zagreb with a friend in 2015.

They were motivated by a US science TV show called "Brain Games" to develop a venue where guests could be delighted while engaging their grey cells – but they now have licensed franchisees from New York to Kuala Lumpur.

The museum features hundreds of optical illusions on exhibit, such as the popular "Head on a Platter," the "Ames chamber," which has an Alice in Wonderland effect on the size of the individuals in it, and the anti-gravity room.

"I nearly fell down, I had to climb all the time," admits nine-year-old Dora, excited by her weightless experience.

Yousfi Mezyan, a 22-year-old French student who visited the museum with a friend, said he enjoyed how the displays "made you think a little bit."

This is not a 'classical' museum

Much to the astonishment of its founders, the museum was an instant success, with over 100,000 visitors in the first year making it Zagreb's most popular museum.

Success in Zagreb opened the way for further expansion, first throughout Croatia, then into European capitals such as Vienna, Belgrade, and Paris.

"Since then, we have not yet stopped. Today, there are 30 museums everywhere around the world", according to Zivkovic,

Branches are fully operational on four continents, with six additional franchises planned to debut by the end of the year, including one in Israel.

According to Zivkovic, they did not choose to create a "classical museum" where visitors are supposed to stay silent and examine exhibits, but rather one where viewers are encouraged to have fun. Another key element of their plan is to encourage people to post photographs online.

"We want the exhibitions to amuse and educate people, but we also want them to be attractive so people can share them on social media," explains Zivkovic.

Countless posts speak to the sharability of activities like "Walking on the Ceiling." And the coronavirus epidemic hasn't hindered Zivkovic's zeal for growth. South America and Australia do not have a Museum of Illusions, he claims, but they will soon.