The city has a total area of 4.50 square miles, including 4.33 of land and 0.17 of water.<ref>https://web.archive.org/web/20120702145235/http://www.census.gov/geo/www/gazetteer/files/Gaz_places_national.txt</ref> Like the rest of the county, Fredericktown lies within the St. Francois Mountains, though it is on relatively flat terrain between Saline Creek, which flows east to west just north of downtown, and the Little St. Francois, which the Saline flows into a short distance to the west. Its average elevation is 741 feet. The city is surrounded on the east, west, and south by a portion of the Mark Twain National Forest. | The city has a total area of 4.50 square miles, including 4.33 of land and 0.17 of water.<ref>https://web.archive.org/web/20120702145235/http://www.census.gov/geo/www/gazetteer/files/Gaz_places_national.txt</ref> Like the rest of the county, Fredericktown lies within the St. Francois Mountains, though it is on relatively flat terrain between Saline Creek, which flows east to west just north of downtown, and the Little St. Francois, which the Saline flows into a short distance to the west. Its average elevation is 741 feet. The city is surrounded on the east, west, and south by a portion of the Mark Twain National Forest. |