Several replacement courthouses were built during the late 19th century and several votes to move the county seat to Mayville narrowly failed.

[4] Construction of the current county building began in 1905; it is now listed on the National Register of Historic Places.

[3][6] Traill County lies on the east side of North Dakota.

The Goose River flows eastward through the center of the county to discharge into the Red.

The northward-flowing Red River forms the eastern boundary line of the county on its way to the Hudson Bay, and the Elk River flows south-southeastward through the southwestern part of the county.

[7] The terrain slopes to the east and north, with its highest point on the lower western boundary line, at 1,201 ft (366 m) ASL.