The Downtown East St. Louis Historic District is a historic commercial district in downtown East St. Louis, Illinois. The district includes 35 buildings, 25 of which are contributing buildings, along Collinsville Avenue, Missouri Avenue, and St. Louis Avenue; all but one of the buildings was historically used for commercial purposes. While development in the area dates back to the late 19th century, the first of the extant buildings in the district were built around 1900 after a tornado devastated the area in 1896. By 1910, the area had become a prosperous commercial district with stores, offices, and entertainment venues; surviving buildings from this period include the Murphy Building and the Cahokia Building. Another large building boom took place in the 1920s, adding buildings such as