The El Pueblo Branch Library is a public library that serves more than half a million residents in the city of Tucson, the county seat of Pima County, Arizona. It is an affiliate branch of the Pima County Public Library (PCPL), founded in 1883 and officially opened to the public in 1886 with only 800 books to start with, and was fondly known as Library Hall. In 1901, a new library administered by the City of Tucson was opened and named the Carnegie Free Library. Furthermore, the library name has been changed several times, and in 2006, when Pima County gained administrative control, it was changed to Pima County Public Library. In response to the escalating demand for library services, the El Pueblo Branch Library was opened in 11975. Fast forward to 2021, when the new 17,700-square-foot space was opened, a standalone 3,500-square-foot structure inside the El Pueblo Community Center, which offers support services for neighboring communities such as a recreation center, literacy programs, and a health clinic. Today, it contributes to the county system's entire resources, which include nearly one million books and serial volumes, more than 23,000 e-books, more than 94,000 audio files, and more than 130,000 video files. Furthermore, there were more than 400,000 registered borrowers, nearly 4.4 million items circulated annually, and nearly six million people visited the library system each year in all 25 sites.