"Honour for the Unknown": this wall painting on Mohamed Mahmoud Street depicts a homeless child who lost his life on Tahrir Square during the revolution. The painting is the work of Ammar Abu Bakr, who says, "Our walls show the truth, and the book 'Walls of Freedom' serves as our tool to share the events of the revolution with the world."

The book "Walls of Freedom" was published in 2013 and shows works of graffiti dealing with the Egyptian Revolution and the events that followed after 2011. The book was published in English by Don Karl, who hails from Berlin, in collaboration with the Egyptian designer Basma Hamdy.

Just as the pharaohs of bygone days immortalised themselves with images on the walls of their temples, modern-day Egyptian artists preserve the memory of the events surrounding the January Revolution on the walls of their cities with graffiti and wall murals. Alaa Awad painted this work of graffiti in memory of thousands of football fans who lost their lives in 2012.

The streets surrounding Tahrir Square have become a gallery for street artists. The graffiti depicted here bears the title "Egyptian Identity" and was painted by Ammar Abu Bakr and Alaa Abd El Hamid. The Arabic calligraphy was provided by Sameh Ismael and the poem was written by Ahmed Aboul Hassan.

In 2011, Mohamed Mahmoud Street in Cairo was the site of bloody clashes between demonstrators and the security forces. Now it is a central part of this art gallery of the revolution. It features a work of graffiti by Abood with the title "State vs. Freedom." Basma Hamdy photographed the piece and published it in "Walls of Freedom."

This is the work of Ammar Abu Bakr and Farik, who belong to the "No Walls" movement. The trompe-l'oeil of a street scene is painted on the blocks of a barricade put up during the revolution to prevent demonstrators from storming the Interior Ministry.

The photographer who works under the pseudonym "El-Zeft" captured this image and named it "Peace Machine." The book "Walls of Freedom" features some 750 photographs and expressive works of graffiti by close to 100 artists. The publication of this book was forbidden in Egypt because it supposedly incites the reader to engage in violence against the government.

Portraits of the heroes of the revolution: "The police would remove a work of graffiti even if it served to honour one of their own men – just as they removed my graffiti of General Batran, who lost his life during the first attacks of the revolution," says Ammar Abu Bakr.

This work of graffiti by the artist Hanaa El Degham ironically portrays the queues of Egyptians waiting to vote. The queue is just as long as that of Egyptians having to wait for gas cylinders, often resulting in skirmishes between those waiting.