Conurbation

A large, continuous urban area formed when neighboring towns or cities grow together while retaining distinct identities.

Urban sprawl: The spread of urban development into surrounding rural or undeveloped land. Outward expansion can close the gaps between neighboring settlements.
Metropolitan area: A city and its economically integrated surrounding communities, often linked by commuting. A metropolitan area is defined by functional ties, not necessarily continuous development.
Urban planning: The practice of guiding land use, infrastructure, and development in urban areas. Planning must coordinate growth across settlements that have physically joined.
Greater London Built-up Area: The continuous built-up area centered on London and extending into surrounding settlements. It illustrates an urban region whose physical extent crosses local authority boundaries.
Suburbanization: The growth of population and development in suburbs beyond a central city. Suburban growth can connect a city to nearby towns.
Megalopolis: A vast region containing several metropolitan areas connected by urban development and transport. It describes a larger scale than a single conurbation.
Regional planning: Planning that coordinates development and infrastructure across a region spanning multiple local jurisdictions. Conurbations often extend beyond the boundaries of any one municipality.
Randstad: A polycentric urban region in the western Netherlands, encompassing cities including Amsterdam, Rotterdam, The Hague, and Utrecht. Its cities remain distinct while forming a closely connected urban region.
Urban morphology: The study of the physical form and spatial structure of urban settlements. It describes the patterns through which a conurbation takes shape.
Agglomeration: A cluster of nearby towns or cities considered together as an urban unit. The term can describe clustered settlements without requiring continuous built-up land.

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MegacityRelated: A conurbation describes connected urban form, not a population threshold.