Infinite-dimensional linear port-Hamiltonian systems on a one-dimensional spatial domain with full boundary control and without internal damping are studied. This class of systems includes models of beams and waves as well as the transport equation and networks of nonhomogeneous transmission lines. The main result shows that well-posed port-Hamiltonian systems, with state space L 2 ((0, 1); C n ) and input space C n , are exactly controllable.invertible matrix for a.e. ζ ∈ (0, 1). We suppose the technical assumption that S −1 , S, ∆ : [0, 1] → C n×n are continuously differentiable.Equation (1) describes a special class of port-Hamiltonian systems, which however is rich enough to cover in particular the wave equation, the transport equation and the Timoshenko beam equation, and also coupled beam and wave equations each with possibly damping on the boundary. For more information on this class of port-Hamiltonian systems we refer to the monograph [1] and the survey [2]. However, we note that here we always assume that there is no internal damping (the matrix P 0 is skew-adjoint) and that we have full boundary control ( W B is a full row rank n × 2n-matrix).Port-based network modeling of complex physical systems leads to port-Hamiltonian systems. For finite-dimensional systems there is by now a wellestablished theory [3,4,5]. The port-Hamiltonian approach has been extended to the infinite-dimensional situation by a geometric differential approach [6,7,8,9] and by a functional analytic approach [10,9,1,11,12,2]. Here we follow the functional analytic point of view. This approach has been successfully used to derive simple verifiable conditions for well-posedness [13,10,9,1,11,14], stability [1,15] and stabilization [16,17,15,18] and robust regulation [19]. For example, the port-Hamiltonian system (1) Provided the port-Hamiltonian system (1) is well-posed, we aim to characterize exact controllability. Exact controllability is a desirable property of a controlled partial differential equation and has been extensively studied, see for example [20,21,22]. We call the port-Hamiltonian system exactly controllable, if every state of the system can be reached in finite time with a suitable control input. Triggiani [23] showed that exact controllability does not hold for many hyperbolic partial differential equations. However, in this paper we prove, that the port-Hamiltonian system (1) is exactly controllable whenever it is well-posed.