100th Meridian Oklahoma/Texas State Line

Harmon County · on US-62, four miles west of Hollis

The Adams-Onís Treaty (1819) designated the 100th Meridian as the boundary between the United States and New Spain (Spanish Mexico). The location of the 100th Meridian remained under dispute after the admission of Texas into the Union in 1845. In 1927, the US Supreme Court confirmed the 100th Meridian as the Oklahoma-Texas border and assigned engineer Samuel S. Gannett to locate and mark the state line.

TodayHistorical map

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David Rumsey Map Collection, Stanford Libraries

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under a mile from where William Gabby lived in the 1760s

what this marker records spans 1777 to 1789, overlapping William Gabby's years here

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Marker data: Oklahoma Historical Society, Historical Marker Program. Marker texts and locations come from the Society's marker database, reproduced with the Society's written permission.
Sponsored by 100th Meridian Chapter Daughters of the American Revolution
This marker on the program's own site

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