- This paper presents a methodology to identify and locate critical links in a grid street network system for feeder transit services. A 'critical' link can be defined as that link which when eliminated from or appended to an existing network would cause the largest change in the network connectivity and consequently transit performance. The most significant contribution of this study is to present a simple analytical approach in locating the critical link(s) for a grid street network system of any size. Easily computable formulas have been provided and validated by simulation analyses. Useful insights indicate a monotonic decrease in link criticality as we depart from the centrally located links to those located at boundaries.