Herculaneum is a city in Jefferson County, Missouri, United States. The population was 3,468 at the 2010 census. The City of Herculaneum was the first county seat of Jefferson County from January 1, 1819 to 1839. The city celebrated its bicentennial throughout 2008. On August 21, 2017, the city of Herculaneum experienced two minutes and 32 seconds of totality during the Great American Eclipse of the Sun. The 2017 total solar eclipse was the first total eclipse in Herculaneum since 1442.
The city received the "Tree City USA" designation by the Arbor Day Foundation for 11 consecutive years, 2007 through 2017. The city is the honorary hometown of the 40th Airlift Squadron, "The Screaming Eagles," from Dyess Air Force Base in Texas.