Developing a GIS-Based Toolbox for Urban Rail Transit Route Identification Dr. Ashish Verma Transportation Planner Mumbai Metropolitan Region Development Authority, India Email: rsashu@yahoo.com This paper discusses an approach for developing a user-interactive GIS-based Toolbox, which is used for optimally aligning urban rail transit system within integrated framework, on demand-oriented corridor on a city transport network. The Toolbox basically implements a Heuristic Rail Transit Corridor Identification Algorithm (HRTCIA) in GIS software TransCAD using GIS Developer’s Kit (GISDK), which is a free form macro programming language using which applications can be developed in TransCAD. Thane City, which is a part of Mumbai Metropolitan Region (MMR) India, was taken as the case study to implement the Toolbox.