[citation needed] On August 25, 1923, an estimated 10,000[7]–30,000 members of the Ku Klux Klan (from surrounding areas) marched there to celebrate a so-called "Karnegie Day" and target the heavily-Catholic town's residents.

The march was resisted by local residents, resulting in a riot which left injuries on both sides and the death of a Klansman.

[8][9] In the 1970s, Carnegie suffered economically with the closure of the great steel mills such as J & L in and around Pittsburgh.

[citation needed] In 2004, Carnegie was significantly damaged by flooding as a result of Hurricane Ivan.

According to the United States Census Bureau, the borough has a total area of 1.6 square miles (4.1 km2), all land.

Carnegie is a walkable community with many interesting and unique stores and restaurants on its Main Street.

The Andrew Carnegie Free Library & Music Hall is home to the Grand Army of the Republic Cpt.

Off the Wall Productions theater also makes its home in Carnegie, and hosts the annual Pittsburgh New Works Festival.

Carnegie also has many local fraternal organizations including the VFW, FOE, American Legion, Elks, Polish Eagles, Polish Sportsmen, AOH, Ukrainian-American Citizens' Club, plus a number of smaller clubs.