An artist shows her hands after working on a wall as part of a campaign to call for coexistence and the renouncement of violence through the painting of walls in Sanaa, Yemen March 15, 2015. (Photo by Mohamed al-Sayaghi/Reuters)

A Chinese tourist visits the Mutianyu Great Wall covered in snow on February 23, 2021 in Beijing, China. Affected by the new coronavirus (COVID-19), the number of visitors to Mutianyu Great Wall in 2020 dropped by about 60%. (Photo by Lintao Zhang/Getty Images)

A dump truck carrying cleaning workers drives on Havana's malecon as a wave crashes on the sea wall, in Cuba, Tuesday, January 24, 2017. Due to high winds and tides, the sea pushed over the sea wall, flooding low parts of the Vedado neighborhood of Havana. (Photo by Desmond Boylan/AP Photo)

A cat sits on the empty Great Wall on February 23, 2021 in Beijing, China. Affected by the new coronavirus (COVID-19), the number of visitors to Mutianyu Great Wall in 2020 dropped by about 60%. (Photo by Lintao Zhang/Getty Images)

Arcelia Aguilar, a resident of “Hogar Jardin De Los Abuelitos”, receives a hug from her niece Maria Aguilar through “El muro de los Abrazos” (The Wall of Hugs) which is a wall made from plastic sheets to protect against the coronavirus, in San Salvador, El Salvador on September 1, 2020. (Photo by Jose Cabezas/Reuters)

Iranian artist and designer Mehdi Ghadyanloo, with the help of the municipality, is slowly brightening up the city of Tehran one wall at a time. The 33-year old street artist has been painting murals and walls in Tehran for the last 5 years age, during which he’s reported to have painted over one hundred walls.

A woman walks past a mural on a wall along a street in Singapore on February 17, 2021. (Photo by Roslan Rahman/AFP Photo)

A man passes by a wall with graffiti in Beirut, Lebanon, on May 29, 2019. (Photo by Bilal Jawich/Xinhua News Agency/Alamy Live News)