This paper studies the modeling of multimodal choice in a railway/highway system with single park-and-ride service on a linear travel corridor. Commuters choose either auto or railway to directly travel from home to city center, or drive to the park-and-ride facility and transfer to railway transit service. Both the traffic congestion on highway and crowding effect on rail transit are considered. The highway capacity is assumed to be stochastic to take into account the travel time reliability for using auto mode. Commuters are assumed to be uniformly distributed along the corridor. A linear complementarity system is proposed to model the commuters’ modal choice along the corridor and solve the spatial equilibrium travel pattern. The formulated linear complementarity system is transformed into a mixed integer linear program to be solved. The modeling approach and solution algorithm are implemented in a small numerical example.