Clarksville is a city in Johnson County, Arkansas, United States. As of the 2010 census the population was 9,178, up from 7,719 in 2000. As of 2018, the estimated population was 9,743. The city is the county seat of Johnson County. It is nestled between the Arkansas River and the foothills of the Ozark Mountains, and Interstate 40 and US Highway 64 intersect within the city limits. Clarksville-Johnson County is widely known for its peaches, scenic byways and abundance of natural outdoor recreational activities. The community began as settlers arrived to the Arkansas Territory. After the Osage tribe was relocated by treaty, Cherokee settlers came to Arkansas by 1800 and primarily lived along the Arkansas River.
Indian trading factors such as Matthew Lyon established their offices at Spadra,on the west end of Lake Dardanelle on the Arkansas River, a Clarksville location now occupied by Spadra Marina. A historical marker, dedicated in 1984, sits on Spadra Bluff, near the original river town of Spadra. The area was reserved for the Cherokee, so most early settlers of Johnson County did not move into the area until after 1828, the year the Cherokee gave up their land. Spadra was the first county seat of Johnson County, convenient to steamboat lines. However when stagecoach and train transportation became more common, land routes from Little Rock to Fort Smith were directed along higher elevations through Clarksville.
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