Citation: Sharma, S.; Ram, S. Investigation of Road Network Connectivity and Accessibility in Less Accessible Airport Regions: The Case of India. Sustainability 2023, 15, 5747. https://doi.org/10.3390/ su15075747 Academic Editors: Piotr Rosik, Bartlomiej Rokicki and Andrzej Szarata Received: 26 October 2022 Revised: 2 February 2023 Accepted: 4 February 2023 Published: 25 March 2023 Copyright: © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). sustainability Article Investigation of Road Network Connectivity and Accessibility in Less Accessible Airport Regions: The Case of India Shalvi Sharma * and Sewa Ram * Transport Planning Department, School of Planning and Architecture, New Delhi 110002, India * Correspondence: sshalvisharma@gmail.com (S.S.); s.ram@spa.ac.in (S.R.) Abstract: One of the keys to the transformation of a region is the expansion of transportation networks. Airports will continue to develop as significant growth centres. The literature review in this article suggests various concepts of importance for connectivity while stating the significance of airport corridors as emerging economic corridors. The objective of this article is to calculate the landside connectivity for road networks for different tiers of airports in their influence areas, as well as to identify the regions that are most and least accessible in the Indian context. This study analysed geographical aspects based on graph theory and the connectivity indices of road networks. The airports were ranked based on these connectivity indices, resulting in the selected case of Bagdogra Airport, West Bengal being used for accessibility analysis. This study also includes centrality indices to determine accessibility in the airport region based on QGIS tools. The centrality indices increase with distance from the airport, indicating the impact of airport connectivity in the identified influence area. The results show critical nodes and links, indicating the necessity for comprehensive planning for new airport regions for greater accessibility and for stimulating development. Keywords: airport region; connectivity; accessibility; nodes; centrality 1. Introduction The ability to connect by air may be crucial in promoting regional economic growth and advancing the long-term goals of national economies. Air connectivity facilitates a country’s integration into the global economy by facilitating the movement of people, ideas, products, and services, as well as financial investments. Airports are essential for transport hubs operating in multiple local, state, national, and international transport networks because they are not silos. Because of this, improving airport accessibility is crucial for the entire value chain. Whether on a trip for business or pleasure, it never ends at the airport. Therefore, air connectivity provides immediate benefits to those who utilise aviation services and larger benefits to the economy as a whole due to its positive effects on produc- tivity and economic performance. As a result of these advantages, governments should research the influence of their policies on air connectivity and the factors that contribute to better air connectivity outcomes [1]. As we respond to the difficulties of deteriorating road congestion and its influence on travel time and travel time reliability, the availability of mass transportation to connect airports throughout the world will become increasingly vital [2]. For a long time, the air transport industry has doubled in size every fifteen years, rising faster than the majority of other industries. As per a report [3], since 1960, the demand for passenger and freight services has increased in tandem with technological advancement and investment. This increase in air travel contrasts favourably with the global GDP, the broadest measure of worldwide output, which increased in real terms by more than five times over the same time span. “Asia/Pacific continued to be the most active region, making up 35% of all revenue-based traffic followed by Europe and North America, each with 26% and 22%” [3]. In their report, the International Air Transport Association Sustainability 2023, 15, 5747. https://doi.org/10.3390/su15075747 https://www.mdpi.com/journal/sustainability