Clustering algorithms have been widely used in wireless sensor networks for virtual backbone construction. They organize the nodes into smaller groups and form a structured topology allowing more efficient bandwidth usage and battery consumption. As the clustering algorithms are usually used for routing, it is crucial to measure the efficiency of the generated backbone in information transport. Failure to do so will impact the routing performance and reduce the reliability of the system. This paper investigates whether the backbone formed by clustering algorithms is able to preserve the routing paths of the network. This property is evaluated by comparing the performance of several clustering algorithms with respect to the average path length. In order to obtain accurate results, the performance is investigated under different network sizes as well as network densities. © 2014 IEEE.