Xiong and Liu [21] gave a characterization of the graphs G for which the n-iterated line graph Ln(G) is hamiltonian, for n ≥ 2. In this paper, we study the existence of a hamiltonian path in Ln(G), and give a characterization of G for which Ln(G) has a hamiltonian path. As applications, we use this characterization to give several upper bounds on the hamiltonian path index of a graph.
