The building in this picture may look like it's melting, but it was actually a temporary mural created by artist Pierre Delavie in 2007. Located at 39 Avenue George V in Paris, France, this building was under construction at the time this photo was taken. To conceal the construction site, Delavie designed a printed canvas to look like a distorted building and draped it over the real building's facade.

Also located in Paris, France, this building sits behind a grassy bank near the Sacré-Cœur Basilica at the summit of Montmartre. According to travel bloggers Brenna Holeman, of This Battered Suitcase, and Sophie Nadeau, of solosophie, you can find this orange building while climbing the steps to get to the Sacré-Cœur. Since you're scaling a hill, when you take a photo of this building, it will be partially covered by the grassy bank at a 45-degree angle. To create the illusion that the house is "sinking," simply rotate your camera until it's parallel with the bank - the ground will appear flat instead of at an angle. You can also take a normal photo and edit it later for the same effect.

A popular tourist destination in Odessa, Ukraine, this so-called "Flat House" is also known as the "Devil's House" or the "Witch House." In real life, it just looks like a regular row of apartments. But from certain angles, the side of the building seems to disappear, creating a mind-boggling visual trick.

Despite what it looks like, the people in this photograph aren't casually sitting on window sills, many feet above the ground. There's a simple explanation for all of this. Those people were all lying on the ground. First built in 2004 for the annual "Nuit Blanche" art festival in Paris, France, "Bâtiment" is a temporary installation created by Argentinian artist Leandro Erlich. The illusion is created by a giant mirror positioned at a 45-degree angle over a house facade on the ground. The mirrored effect looks like a three-dimensional house in photos, so participants can pretend like they're dangling from windows, scaling the side of the building, and more. Erlich's installation has also appeared at the London Architecture Festival in 2013, where these photos were taken, among others.

Famed architect Vlado Milunic collaborated with Canadian-American architect Frank Gehry to design this famous building in Prague, Czech Republic. Known as the "Dancing House," the two buildings represent two iconic dancers, Fred Astaire and Ginger Rogers. The glass tower, "Ginger" was designed to bend toward the concrete tower, "Fred," which is topped with a metal cupola to represent hair.

These cube houses can be found in the cities of Rotterdam and Helmond in the Netherlands. Designed by architect Piet Blom, these homes were inspired by the concept of "living as urban roof," a model of community living that optimizes the limited space available in densely populated, urban cities. From the outside, it may be difficult to picture normal rooms inside these cube houses, but the illusion disappears once you're inside. While the walls of the home are angled, the floor is perfectly flat. If you're especially intrigued, you can evenbook a stay at one of these cube homes on Airbnb.

Made of 400 individual tiles, the floor in this building looks like it has a giant dent in the middle, but it's actually completely level. Created by UK-based tile company Casa Ceramica, the optical illusion was designed to stop people from running in the hallway. It's installed in the entrance to one of the company's showrooms in Manchester, UK. Even more mind-boggling, the optical illusion only works when you face the showroom's entrance. The "dent" in the floor disappears when you look at it from the opposite perspective. Even more mind-boggling, the optical illusion only works when you face the showroom's entrance. The "dent" in the floor disappears when you look at it from the opposite perspective.