Jet collimation profile in NGC 315. Left panel: VLBI data at different frequencies. A transition from a parabolical to conical jet shape is observed on sub-parsec scales. The fitted red line is a broken power-law. The dotted lines delimit the uncertainty interval of the transition distance. The latter is much smaller than the estimated Bondi radius. Right panel: VLBI and VLA data. After the transition, the global jet shape remains conical beyond the Bondi radius and up to Megaparsec distance from the black hole.