  We update the constraints on the location of the nearest UHECR source. By
analyzing recent data from the Pierre Auger Observatory using state-of-the-art
CR propagation models, we reaffirm the need of local sources with a distance
less than 25-100 Mpc, depending on mass composition. A new fast semi-analytical
method for the propagation of UHECR in environments with turbulent magnetic
fields is developed. The onset of an enhancement and a low-energy magnetic
horizon of cosmic rays from sources located within a particular distance range
is demonstrated. We investigate the distance to the nearest source, taking into
account these magnetic field effects. The results obtained highlight the
robustness of our constrained distances to the nearest source.
