Jefferson County
URL: https://knowledge.ivjn.us/en/places/mo-jefferson-county.html

Jefferson County is a county of Missouri, United States.

## Overview

Jefferson County is a county of [Missouri](https://knowledge.ivjn.us/en/places/missouri.html), United States (FIPS mo099), with a population of about 226,739[^geonames].

## Geography

- Coordinates: 38.2611, -90.5377
- Time zone: America/Chicago

Updated: 2026-10-29

Relations:
- Located in: Missouri https://knowledge.ivjn.us/en/places/missouri.html
- Contains places: Arnold https://knowledge.ivjn.us/en/places/mo-arnold.html
- Contains places: Barnhart https://knowledge.ivjn.us/en/places/mo-barnhart.html
- Contains places: Byrnes Mill https://knowledge.ivjn.us/en/places/mo-byrnes-mill.html
- Contains places: Cedar Hill Lakes https://knowledge.ivjn.us/en/places/mo-cedar-hill-lakes.html
- Contains places: Cedar Hill https://knowledge.ivjn.us/en/places/mo-cedar-hill.html
- Contains places: Crystal City https://knowledge.ivjn.us/en/places/mo-crystal-city.html
- Contains places: De Soto https://knowledge.ivjn.us/en/places/mo-de-soto.html
- Contains places: Festus https://knowledge.ivjn.us/en/places/mo-festus.html
- Contains places: Herculaneum https://knowledge.ivjn.us/en/places/mo-herculaneum.html
- Contains places: High Ridge https://knowledge.ivjn.us/en/places/mo-high-ridge.html

Mentioned in:
- Arnold https://knowledge.ivjn.us/en/places/mo-arnold.html
- Barnhart https://knowledge.ivjn.us/en/places/mo-barnhart.html
- Byrnes Mill https://knowledge.ivjn.us/en/places/mo-byrnes-mill.html
- Cedar Hill https://knowledge.ivjn.us/en/places/mo-cedar-hill.html
- Cedar Hill Lakes https://knowledge.ivjn.us/en/places/mo-cedar-hill-lakes.html
- Crystal City https://knowledge.ivjn.us/en/places/mo-crystal-city.html
- Festus https://knowledge.ivjn.us/en/places/mo-festus.html
- Herculaneum https://knowledge.ivjn.us/en/places/mo-herculaneum.html
- High Ridge https://knowledge.ivjn.us/en/places/mo-high-ridge.html
- Hillsboro https://knowledge.ivjn.us/en/places/mo-hillsboro.html

Sources:
- GeoNames US dataset (US.txt / admin2Codes.txt) https://download.geonames.org/export/dump/US.zip