A method that generated choice sets for commuters in the Munich, Germany, metropolitan area was explored. The method used Global Positioning System trajectories and interview data from 300 commuters over an 8-week survey to combine chosen, known, and generated routes into choice sets for route choice modeling. The method used revealed preference routes as well as stated preference routes to calculate accepted detour factors, which were then used as boundary conditions for choice set generation using path enumeration. On the basis of a spatial choice set, the method generated time-dependent choice sets by attributing all routes with actual travel times at the time traveled.