If there is one requirement of architecture, it's that the structure must remain upright. Forget any aesthetic purpose, architects would be out of a job if their buildings continually failed to meet this one test. Yet some architects push the boundaries, seemingly daring with Newton's universal law of gravity, to design buildings that not only appear to defy logic, but are beautiful at that. From a cantilevered barn designed by the Dutch-based firm MVRD to an impressively stacked building in Hanover, Germany, by the Stuttgart-based firm Behnisch Architekten, these 12 buildings seem impossible to conceive, let alone build. Of course, all of these structures passed strict zoning laws before they were erected. What is not guaranteed, however, is whether merely looking at them will cause you vertigo.

Photo: Getty Images/Eduardo Garcia

Building: Museum of Tomorrow

Location: Rio de Janeiro, Brazil

Architect: Santiago Calatrava

Fun fact: Completed in 2015, 1.4 million people visited the Museum of Tomorrow during its inaugural year, far exceeding the anticipated 450,000 visits. It is currently the most-visited museum in Brazil.

Photo: Getty Images/Kurita KAKU

Building: Takasugi-an (Tea house on the Tree)

Location: Chino, Nagano Prefecture, Japan

Architect: Terunobu Fujimori

Fun fact: The name Takasugi-an means, “a tea house [built] too high.”

Photo: Getty Images/ullstein bild

Building: MARTa Herford

Location: Herford, Germany

Architect: Frank Gehry, Hartwig Rullkötter

Fun fact: The art museum has a statue of Tupac Shakur at the entrance

Photo: Getty Images/anouchka

Building: Dancing House

Location: Prague, Czech Republic

Architect: Frank Gehry

Fun fact: The inspiration for the structure originally came from the famous dancers Fred Astaire and Ginger Rogers.

Photo: Getty Images/Martin Kirchner

Building: NORD/LB Bank

Location: Hanover, Germany

Architecture firm: Behnisch, Behnisch & Partner

Fun fact: The bank has invested in an extensive art collection, including some 3,000 works by such postwar artists as Georg Baselitz, Gerhard Richter, Sol LeWitt, Jeff Koons, and Jannis Kounellis, among others. The works are displayed within the several company buildings.

Photo: Hufton & Crow

Building: Learning Hub at the Nanyang Technological University

Location: Singapore

Architecture firm: Heatherwick Studio

Fun fact: The design was meant to rethink the ways in which academic buildings are built, allowing students and professors to more easily interact in an open environment.

Photo: Courtesy of MVRDV

Building: Ragnarock

Location: Roskilde, Denmark

Architecture firms: MVRDV and COBE

Fun fact: The city of Roskilde is filled with old cement factories, which makes the design for Ragnarock, a museum dedicated to rock music, all the more exciting.

Photo: Getty Images/David Giral Photography

Building: Odeillo Solar Furnace

Location: Font-Romeu-Odeillo-Via, France

Fun fact: The Odeillo solar furnace is the world's largest solar furnace. The location was selected because of the duration (more than 2,500 hours per year) and the quality of sunlight that hits the area.

Photo: Getty Images/Kloeg008

Building: Cube Houses

Location: Rotterdam, Holland

Architect: Piet Blom

Fun fact: The design for the 38 homes was meant to represent a village within a city, but practically speaking, the design was intended to optimize the space inside of the home set in an urban space.

Photo: Getty Images/Jeff Greenberg/UIG

Building: One Central Park

Location: Sydney

Architect: Jean Nouvel

Fun fact: With a mix of various plants and flowers on the structure's exterior reaching nearly 165 feet high, the building's vertical hanging garden is the tallest in the world.

Photo: Getty Images/saiko3p

Building: Heydar Aliyev Center

Location: Baku, Azerbaijan

Architect: Zaha Hadid

Fun fact: The significance of the structure's swooping design is all the more important, as it's a distinct departure from the rigid Soviet-era architecture that once defined the region.

Photo: Getty Images/View Pictures/UIG/Edmund Sumner

Building: Balancing Barn

Location: Thorington, England

Architecture firm: MVRDV

Fun fact: One one end of the home, visitors inside the space can experience nature at ground level. On the other end, however, they are able to view the world as if they were at tree height, a phenomenon that occurs without the visitor having to climb a set of stairs.