Texarkana's most photographed sign outside The United States Post Office and Courthouse. ID: 2894 | This file appears in: The Two-State City with a Four-States Fair The Texas- Arkansas state line runs through the center of the building. The west side serves Texas, while the east side serves Arkansas. | Source: Image Credit: The Advertising and Promotion Commission of Texarkana, Arkansas. https://www.ourtexarkana.com/attractions/state-line-post-office. Download Original File SourceImage Credit: The Advertising and Promotion Commission of Texarkana, Arkansas. https://www.ourtexarkana.com/attractions/state-line-post-office. "Texarkana's most photographed sign outside The United States Post Office and Courthouse." appears in: The Two-State City with a Four-States Fair