Transportation planning is an important part in the development of a region. An effective transport system and associated urban forms will improve the economic and social opportunities. Accessibility and mobility are the two main parameters which contribute to the effective transportation system. In this paper, the accessibility to the public transportation system is identified for the selected study area with the help of an indexing system. The sub-area in the region was thus graded based on their accessibility and the obtained values are found to resemble the real world. Keywords-Accessibility, indexing system, public transport system, transport planning I. I nt roduct io n Accessibility is concerned with the opportunity that an individual or type of person at a given location possesses to take part in a particular activity or set of activities. Accessibility takes on board the land use- transport connection and handles trip numbers and travel time as indicators. Measurement of access to social services for each household can help in adjust and better accommodate under-served regions. Important factors affecting accessibility are mobility, transport options, land use, and affordability. Affordability of a transit depends on the ability of the person to pay the cost for the particular trip. Public transit system development is focused on providing equal opportunity to all these economic groups. Thus the system should be accessible to all economic groups. Accessibility can be directly related to both the qualities of the transport system like the travel speed, and the qualities of the land use system like densities and mixes. At the same time it can also be directly related to economic goals (access to workers, customers, suppliers), social goals (access to employment, goods, services, social contacts), and environmental goals (resource-efficiency of activity/mobility patterns). The present study focuses on the accessibility to public transportation system in the selected area. II. Scope and Objectives of the Work The scope of the present paper is confined to measurement of accessibility levels of the population in the Central Business District (CBD) areas in Thiruvananthapuram City, Kerala to public transportation. The paper addresses the following two objectives: 1. To know about the different levels of accessibility to the public transportation system. 2. To prepare an accessibility index for the proposed area. III. Findings from Earlier Studies Accessibility is a term used in transport and land-use planning, and is generally ease of reaching. Accessibility is the suitability of the transit system in helping people get to their destinations in a reasonable amount of time. It is a function of the mobility of the individual, spatial location, opportunities relative to the starting point of the individual, and the times at which the individual is able to participate in the activity. Accessibility helps in identifying the interrelation of transport and land-use. Accessibility measures can be grouped into five categories: travel-cost approach, gravity or opportunities approach, constraints-based approach, utility-based surplus approach, composite approach. The gravity or opportunities approach summarises the contour or cumulative opportunity and gravity models. The constraint-based approach is equivalent to time-space measures, while the utility-based surplus approach uses the utility measures with a greater focus on individual behaviour and decision-making. Composite approaches attempt to combine time-space and utility indicators into a common model. In a paper regarding Advances in public transport accessibility assessments for development control, Public Transport Accessibility Level (PTAL)is one of the criteria for evaluating the accessibility PTAL is calculated by summing a series of indices for bus, train, underground and rail services to obtain an Index Number was explained by (G Christopher and S Geoff),2008 (1). The Index Numbers are compared with a banding regime to obtain a PTAL grade. Walk distance, the number of services and their frequency, walking