  In this article, we introduce Cohn path algebras of higher-rank graphs. We
prove that for a higher-rank graph $\Lambda $, there exists a higher-rank graph
$T\Lambda $ such that the Cohn path algebra of $\Lambda $ is isomorphic to the
Kumjian-Pask algebra of $T\Lambda $. We then use this isomorphism and
properties of Kumjian-Pask algebras to study Cohn path algebras. This includes
proving a uniqueness theorem for Cohn path algebras.
