Murals are urban art, living art, street art, often social art, and almost always communal. They may be planned by a particular artist and then painted by a team, or may come from an economically poor community in response to an event.
Los Angeles has interesting ones.
Chicanos especially have painted them to remedy the lack of representation or the inadequate representation of Mexican-Americans in the city. The Great Wall of Los Angeles is one such project. Noemi Garcia's art site, Painted City, talks about the creation of these murals of the Great Wall --which tell some of the history of the city and especially its Mexican-American inhabitants-- and about the diverse artists who painted them, people from many neighborhoods and backgrounds. There are some links to reproductions, including this one, which depicts the way the freeways divided the barrio . (This occurred in many other places in the U.S. When I was interviewing Catholic women in Texas in the 198os I heard similar stories from Mexican-Americans there.)
And the one below, unlike most of the others here, is an indoor mural, and one made by women. I'm pasting here the text accompanying it on the website where I found it. Thanks to MCHA ( Maternal Child Health Access)In the summer of 2004, Jose Ramirez, a renowned Los Angeles-based artist (http://www.ramirezart.com/), led an indoor mural project for Maternal and Child Health Access (MCHA). Eight women from our case-management program and arts-and-crafts collective took part in this adventure and whether participating or just observing the process, it was an amazing experience for everyone in our office. Initially, the women did not believe they would ever draw or paint, let alone fill what appreared to be an enormous canvas with their art. Jose met this challenge by teaching them basic art techniques and coaching them them throughout the process. He constantly encouraged and nurtured the women's artistic abilities, and when they saw their work taking form they resonated with confidence and pride. With breastfeeding babies in slings and children reading or creating their own artwork at tables near the mural site, the women painted beautiful images that reflect a vision for a neighborhood of inclusion that provides education, health care, green areas, and places such as MCHA where they feel safe enough to dream, learn, and take action. The women who created the mural are Manuela Silva, Margarita Velasquez, Dominga Guzman, Yurri Carreon, Hortencia Montiel, Maria Venegas, Teresa Garcia, and Rocio Martinez.