Railway tracks are traditionally modelled as infinitely long beam on elastic foundation. In the present study, the combined effect of foundation nonlinearity and the spatial variation of foundation stiffness on the dynamics of an infinitely long railway track is investigated. Track is modelled as infinitely long beam on nonlinear variable foundation subjected to moving load. Here, the foundation stiffness is varied harmonically along the length of the beam and the nonlinearity is introduced by varying the tensile stiffness of the foundation. Thus, the two extreme cases possible in this study are the linear foundation and perfectly tensionless foundation. Results are obtained with the help of a finite element model which has been analysed with the help of a MATLAB program. This study highlights the effects of foundation nonlinearity and spatial variation of the stiffness on the dynamic response of the railway track. It is interesting to observe that, for the nonlinear foundation, the responses are considerably affected both qualitatively as well as quantitatively with the variation in foundation stiffness wavelength and amplitude.