[1] Indian routes are signed by shields featuring a downward-pointing arrowhead with varying designs depending on the state and/or reservation.

BIA route numbers are used on sign posts, atlas maps, plans, programs, reports, and other bureau records requiring similar identification.

[2] Historically, the term "Indian route" referred to one or more components of an extensive network of trails used by indigenous peoples for war, trade, and migration, long before the advent of railroads and highways.

[3] Oral tradition is usually the major source for route identification, but this is sometimes supplemented by field notes of land-grant surveys, old county maps, and historic narratives from scientists, explorers, soldiers and law enforcement officials.

A section break occurs when it is necessary to accurately report data associated with a change in the nature of the route.