Classical molecular dynamics (MD) simulations of Xe on the basal (0001) face of hexagonal ice at 180 K have been performed in order to investigate the mechanism of adsorption and the initial stage of absorption of a van der Waals particle into crystalline ice. The potential of mean force (PMF) as a function of the relative position of the Xe atom perpendicular to the ice surface is found to increase abruptly as the particle propagates from the disordered outermost region to the deeper hexagonally ordered region. A set of local minima observed in the PMF appears to correspond directly to the layer-by-layer crystal structure of hexagonal ice. Along with the unbound state, the first two minima (with similar free energies) that correspond to the accommodation of the guest particle on and inside the disordered outermost bilayer, respectively, are found to be populated during the MD runs. The multiple transitions of the system among these three states are also observed in accord with the PMF profile, which also suggests that the penetration of any ordered hexagonal bilayer by the Xe atom is unlikely. Furthermore, MD simulations of pristine ice (i.e., without Xe) over a 3-ns simulation period show that the initially perfect-ordered hexagonal crystalline structure of the outermost bilayer undergoes transformation to a noncrystalline phase, in which fragmented domains with hexagonal ordering persist. Moreover, the accommodation of the Xe atom inside the outermost bilayer could facilitate further disordering of the hexagonal structure of this bilayer with the formation of a completely disordered Xe-ice surface phase.