Train-induced ground vibrations pose serious distress in the vicinity of urban railway tracks. The present study intends to characterize the dispersion of train-induced ground vibrations in native sub-soil supporting ballasted high-speed rail lines, at transit speeds of 160–200 km/h. Results from moving load simulations indicate that ground vibrations attenuate rapidly with increase in depth from surface level of ground. However, attenuation of vibration is found to be more gradual along the horizontal surface level of ground. Intense ground vibrations are found to be distributed along a hemi-spherical radial space surrounding the track centreline. However, these vibrations are found to attenuate rapidly in the immediate space close to the railway track, followed by a gradual attenuation at the farther locations in the ground. Isolation of vibrations within the railway embankment and the region of ground supporting the embankment is recommended for effectively mitigating ground-borne railway vibrations. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.