This research focuses on the study of a hub location problem (HLP), specifically immersed in a tree-shaped network.The objective is to find the minimum cost tree network with three sets of nodes: (i) a set of selected hubs, (ii) a set of spokes that are allocated to a single hub, and (iii) a set of so-called \textit{stopovers} that are intermediate nodes located on a path between two hubs. To locate stopovers, it is necessary to relax some assumptions of classical HLPs. The first one to violate is the assumption to have a complete graph of the hubs. In this work, the graph of hubs is a tree. Another assumption to relax is that the link between hubs may form a path traversing a set of stopovers.We present a mixed-integer linear programming (MILP) formulation for the HLP with stopovers on a tree topology. Numerous computational experiments are performed to test the limits of the MILP formulation. We finally present a case study relying on a real river network.