A device includes a database including data related to obstacles, a first determination module for determining at least one obstacle intercepted by a direct flight path connecting an initial point to the target point, a second determination module for determining at least one lateral extreme apex of at least one intercepted obstacle, an evaluation module for assigning a rating to each section corresponding to a segment between a lateral extreme apex and the initial point, a storage module for storing in a memory the section corresponding to the optimum extreme apex having the best rating, the optimum flight path corresponding to all of the sections stored in the memory, the preceding modules being used iteratively, the device further including a transmission module for transmitting the optimum flight path to a user device.