Saint Charles in St. Charles County, Missouri — The American Midwest (Upper Plains)
Old Post Office
Photographed by Craig Doda, September 12, 2026
1. Old Post Office Marker
119 South Main
OPO Startups 2015
Restoration and Adaptive Re-use
U.S. Post Office 1909-1964
U.S. Post Office built in 1912
St. Charles County
Court House 1840-1899
OPO Startups is a place where entrepreneurs can connect, work and collaborate.
Erected by OPO Startups.
Topics. This historical marker is listed in these topic lists: Communications • Government & Politics • Industry & Commerce. A significant historical year for this entry is 2015.
Location. 38° 46.835′ N, 90° 28.911′ W. Marker is in Saint Charles, Missouri, in St. Charles County. It is at the intersection of South Main Street and Madison Street, on the right when traveling south on South Main Street. Touch for map. Marker is at or near this postal address: 119 S Main Street, Saint Charles MO 63301, United States of America. Touch for directions.
Regionally, this marker is in the Missouri River Corridor and in Greater St. Louis. It is also in the American Midwest, in the Lewis & Clark Corridor, in the Corn Belt, and in the Great River Road Region. Globally, it is in North America, the Western Hemisphere,
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Other nearby markers. At least 8 other markers are within walking distance of this marker: 119 South Main (here, next to this marker); 130 South Main (a few steps from this marker); 136 South Main (within shouting distance of this marker); 116-120 South Main (within shouting distance of this marker); 122 South Main (within shouting distance of this marker); 117 South Main (within shouting distance of this marker); 108 South Main (within shouting distance of this marker); 101 South Main (within shouting distance of this marker).
Photographed by Craig Doda, September 12, 2026
2. Old Post Office Marker
Credits. This page was last revised on October 30, 2026. It was originally submitted on October 30, 2026, by Craig Doda of Napoleon, Ohio. This page has been viewed 6 times since then. Photos: 1, 2. submitted on October 30, 2026, by Craig Doda of Napoleon, Ohio. • Andrew Ruppenstein was the editor who published this page.
