Abstract
Sustainable development increasingly hinges on recognizing both the nuance of urban form and the interconnections linking settlements into systems. We compare three global geospatial approaches transcending the urban–rural dichotomy—Degree of Urbanization (DEGURBA), Urban–Rural Catchment Areas (URCA), and Multi-Tier City–Regions (MTCR)—and examine how they relate form, accessibility, and function at system scale. Highlighting the importance of peri-urban areas, small and intermediate cities, and multi-tier connectivity, these approaches challenge institutional structures organized around an urban–rural divide. We conclude by outlining four research frontiers.
Similar content being viewed by others
Data availability
No datasets were generated or analyzed during the current study.
References
Van Vliet, J. Direct and indirect loss of natural area from urban expansion. Nat. Sustain. 2, 755–763 (2019).
Hutchings, P. et al. Understanding rural–urban transitions in the Global South through peri-urban turbulence. Nat. Sustain. 5, 924–930 (2022).
Zhou, W., Pickett, S. T. A. & McPhearson, T. Conceptual frameworks facilitate integration for transdisciplinary urban science. npj Urban Sustain. 1, 1 (2021).
Espey, J., Parnell, S. & Revi, A. The transformative potential of a Global Urban Agenda and its lessons in a time of crisis. npj Urban Sustain. 3, 15 (2023).
Chen, Z. & Yeh, A. G.-O. Delineating functional urban areas in Chinese mega city regions using fine-grained population data and cellphone location data: a case of Pearl River Delta. Comput. Environ. Urban Syst. 93, 101771 (2022).
Dong, L. et al. Defining a city—delineating urban areas using cell-phone data. Nat. Cities 1, 117–125 (2024).
Louail, T. et al. From mobile phone data to the spatial structure of cities. Sci. Rep. 4, 5276 (2014).
Rozenblat, C., Pumain, D. & Velásquez M. E. International and Transnational Perspectives on Urban Systems (Springer Singapore, 2018).
Sorokin, P. & Zimmerman, C. C. Principles of Rural-Urban Sociology (Henry Holt and Company, 1929).
Bishop, C. E. The urbanization of rural America: implications for agricultural economics. J. Farm Econ. 49, 999–1008 (1967).
United Nations. Demographic Yearbook 1972 (United Nations, 1973).
Vlahov, D. & Galea, S. Urbanization, urbanicity, and health. J. Urban Health 79, S1–S12 (2002).
Champion, T. & Hugo, G. New Forms of Urbanization: Beyond the Urban-Rural Dichotomy https://doi.org/10.4324/9781315248073 (Routledge, 2004).
Dymitrow, M. & Brauer, R. Meaningful yet useless? Factors behind the retention of questionable concepts in human geography. Geogr. Ann. Ser. B Hum. Geogr. 100, 195–219 (2018).
Boone, C. G. et al. Reconceptualizing Land for Sustainable Urbanity. in Rethinking Global Land Use in an Urban Era (eds Seto, K. C. & Reenberg, A.) 313–330. https://doi.org/10.7551/mitpress/10011.003.0023 (The MIT Press, 2014).
Zhaxi, D., Zhou, W., Pickett, S. T. A., Guo, C. & Yao, Y. Urbanity mapping reveals the complexity, diffuseness, diversity, and connectivity of urbanized areas. Geogr. Sustain. 5, 357–369 (2024).
Sorokin, P., Zimmerman, C. & Galpin, C. J. A Systematic Sourcebook in Rural Sociology Vol. 3 (University of Minnesota Press, 1932).
Hoffmann, E. M. et al. Rurbanity: a concept for the interdisciplinary study of rural–urban transformation. Sustain. Sci. 18, 1739–1753 (2023).
Dijkstra, L. & Poelman, H. A Harmonised Definition of Cities and Rural Areas: The New Degree of Urbanisation http://ec.europa.eu/regional_policy/sources/docgener/work/2014_01_new_urban.pdf (2014).
European Commission. Statistical Office of the European Union. Applying the Degree of Urbanisation: A Methodological Manual to Define Cities, Towns and Rural Areas for International Comparisons: 2021 Edition (Publications Office, LU, 2021).
Dijkstra, L. et al. Applying the Degree of Urbanisation to the globe: a new harmonised definition reveals a different picture of global urbanisation. J. Urban Econ. 125, 103312 (2021).
Cattaneo, A., Nelson, A. & McMenomy, T. Global mapping of urban–rural catchment areas reveals unequal access to services. Proc. Natl. Acad. Sci. USA 118, e2011990118 (2021).
United Nations, Department of Economic and Social Affairs, Population Division. World Urbanization Prospects: The 2018 Revision (United Nations, 2019).
OECD. OECD Regions and Cities at a Glance 2024 (OECD Publishing Éditions OCDE, 2024).
Esch, T. et al. Dimensioning urbanization—an advanced procedure for characterizing human settlement properties and patterns using spatial network analysis. Appl. Geogr. 55, 212–228 (2014).
Prieto-Curiel, R., Schumann, A., Heo, I. & Heinrigs, P. Detecting cities with high intermediacy in the African urban network. Comput. Environ. Urban Syst. 98, 101869 (2022).
Nguyen, T. T. et al. Towards large-scale analyses of settlement patterns in urbanizing landscapes—findings of first studies for India, Egypt, and China. Sci. Rep. 14, 25782 (2024).
Cattaneo, A. et al. Worldwide delineation of multi-tier city–regions. Nat. Cities 1, 469–479 (2024).
Schiavina, M. et al. GHSL Data Package 2022—Public Release GHS P2022 https://doi.org/10.2760/19817 (Publications Office of the European Union, 2022).
Schiavina, M., Freire, S. & MacManus, K. GHS-POP R2022A—GHS population grid multitemporal (1975-2030). https://doi.org/10.2905/D6D86A90-4351-4508-99C1-CB074B022C4A (European Commission, Joint Research Centre (JRC), 2022).
WorldPop. Gridded population dataset. (2023).
Rose, A. et al. LandScan Global. https://doi.org/10.48690/1523378 (Oak Ridge National Laboratory, 2020).
WorldPop. Global 1km Population. https://doi.org/10.5258/SOTON/WP00647 (University of Southampton, 2018).
Rozenblat, C. & Pumain, D. A new worldwide typology of cities and systems of cities. In International and Transnational Perspectives on Urban Systems (eds Rozenblat, C., Pumain, D. & Velásquez, M. E.) 1–14 (Springer Singapore, 2018).
Dijkstra, L. & Jacobs-Crisioni. Developing a Definition of Functional Rural Areas in the EU (European Commission, 2023).
Melchiorri, M. et al. The multi-temporal and multi-dimensional global urban centre database to delineate and analyse world cities. Sci. Data 11, 82 (2024).
FAO, IFAD, UNICEF, WFP and WHO. The State of Food Security and Nutrition in the World 2023. Urbanization, Agrifood Systems Transformation and Healthy Diets across the Rural-Urban Continuum (FAO, 2023).
Cockx, L. & Boti, D. Exploring Food Consumption Patterns Across the Rural-Urban Continuum in West Africa (European Commission, 2024).
Sengupta, A., King, A. D. & Ryan, R. G. Inequity in population exposure to accelerated warming. Geophys. Res. Lett. 51, e2024GL110644 (2024).
Schug, F. et al. The global wildland–urban interface. Nature 621, 94–99 (2023).
Wei, S. et al. Coastal urbanization may indirectly positively impact growth of mangrove forests. Commun. Earth Environ. 5, 608 (2024).
Florio, P., Freire, S. & Melchiorri, M. Estimating geographic access to healthcare facilities in Sub-Saharan Africa by Degree of Urbanisation. Appl. Geogr. 160, 103118 (2023).
Schiavina, M. et al. Multi-scale estimation of land use efficiency (SDG 11.3.1) across 25 years using global open and free data. Sustainability 11, 5674 (2019).
Schiavina, M. et al. Land use efficiency of functional urban areas: Global pattern and evolution of development trajectories. Habitat Int. 123, 102543 (2022).
Van Der Borght, R. & Pallares-Barbera, M. Greening to shield: The impacts of extreme rainfall on economic activity in Latin American cities. Glob. Environ. Change 87, 102857 (2024).
Van Strien, M. J. & Grêt-Regamey, A. A global time series of traffic volumes on extra-urban roads. Sci. Data 11, 470 (2024).
Ambikapathi, R. et al. Global food systems transitions have enabled affordable diets but had less favourable outcomes for nutrition, environmental health, inclusion and equity. Nat. Food 3, 764–779 (2022).
Campomanes, F., Marshall, M. & Nelson, A. A method for estimating physical and economic food access at high spatial resolution. Food Secur. 16, 47–64 (2024).
Pelz, S., Chinichian, N., Neyrand, C. & Blechinger, P. Electricity supply quality and use among rural and peri-urban households and small firms in Nigeria. Sci. Data 10, 273 (2023).
Cattaneo, A. et al. Economic and social development along the urban–rural continuum: new opportunities to inform policy. World Dev. 157, 105941 (2022).
Chaplin-Kramer, R. et al. Mapping the planet’s critical natural assets. Nat. Ecol. Evol. 7, 51–61 (2022).
Behrer, A. P. & Heft-Neal, S. Higher air pollution in wealthy districts of most low- and middle-income countries. Nat. Sustain. 7, 203–212 (2024).
Becerra-Valbuena et al. Well-Being Dynamics in Sub-Saharan Africa https://doi.org/10.4060/cd3839en (FAO, 2025).
Malashock, D. A. et al. Estimates of ozone concentrations and attributable mortality in urban, peri-urban and rural areas worldwide in 2019. Environ. Res. Lett. 17, 054023 (2022).
Svobodova, K. et al. Decarbonization, population disruption and resource inventories in the global energy transition. Nat. Commun. 13, 7674 (2022).
Galpin, C. J. The Social Anatomy of an Agricultural Community, University of Wisconsin Agricultural Experiment Station Research Bulletin No. 34 (University of Wisconsin, 1915).
Kolb, J. H. A study in rural community organization. Am. J. Sociol. 29, 34–41 (1923).
Christaller, W. Die Zentralen Orte in Süddeutschland (Central Places in Southern Germany) (Fischer, 1933).
Lösch, A. The Economics of Location (Yale University Press, 1954).
King, L. J. Central Place Theory (West Virginia University, 2020).
Mulligan, G. F., Partridge, M. D. & Carruthers, J. I. Central place theory and its reemergence in regional science. Ann. Reg. Sci. 48, 405–431 (2012).
Girgin, S. et al. Worldwide delineation of multi-tier city-regions. Zenodo, https://doi.org/10.5281/ZENODO.11187634 (2024).
FAO. City–Region Explorer. https://data.apps.fao.org/cityregions/ (2025).
De Simone, L., McMenomy, T., Girgin, S. & Cattaneo, A. Gaining Territorial Insights with the City–Region Explorer https://openknowledge.fao.org/handle/20.500.14283/cd6522en; https://doi.org/10.4060/cd6522en (2025).
Cattaneo, A. & McMenomy, T. City-Region Explorer: video tutorials. https://www.youtube.com/playlist?list=PLzp5NgJ2-dK4rdHDgorerazRDpg9fS7mE (2025).
Esch, T. et al. Digital world meets urban planet—new prospects for evidence-based urban studies arising from joint exploitation of big earth data, information technology and shared knowledge. Int. J. Digit. Earth 13, 136–157 (2020).
Schläpfer, M. et al. The universal visitation law of human mobility. Nature 593, 522–527 (2021).
Kahn, M. E. & Walsh, R. Cities and the environment. In Handbook of Regional and Urban Economics (eds Duranton, G., Henderson, V. J. & Strange, W.) Vol. 5, 405–465 (Elsevier, 2015).
United Nations. World Urbanization Prospects 2025: Summary of Results. UN DESA/POP/2025/TR/NO. 12. (New York: United Nations, 2025).
Author information
Authors and Affiliations
Contributions
A.C. and S.G. contributed equally to the drafting of this Perspective. We confirm that both authors have read and approved the manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
About this article
Cite this article
Cattaneo, A., Girgin, S. Beyond urban and rural: exploring form, accessibility, and interconnectivity in global urban classifications. npj Urban Sustain (2026). https://doi.org/10.1038/s42949-025-00304-x
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s42949-025-00304-x


