In this paper, we present two bicriteria uncapacitated, multiple allocation p-hub location problems. In the first problem, our first objective is to minimize the total transportation costs of the uncapacitated multiple allocation p-hub median problem with a positive interhub transfer cost. Our second objective is to minimize the total traveling costs between hub points and origin–destination points. In this case, the interhub transfer cost is negligible, and the problem turns into a well-known facility location problem, i.e., the p-median problem. In the second problem, we address the delays occurring with the congestion during service at the hubs. We consider the trade-off between our first objective and a new objective function, which is to minimize the maximum delay at each hub. We propose bicriteria evolutionary algorithms to approximate the efficient frontiers of these problems. We test the performance of our algorithm on Turkish Postal System, Australian Post, and U.S. Civil Aeronautics Board data sets.
