What is the term for the process of filling in empty or run-down parts of a city with new development?

The term for the process of filling in empty or run-down parts of a city with new development is known as infill. This process involves the development of vacant or under-utilized land within existing urban areas, aiming to increase density and make better use of available infrastructure. Infill can help to reduce urban sprawl, enhance the vibrancy of neighborhoods, and utilize spaces that would otherwise remain unproductive.

Urban revitalization refers more broadly to efforts aimed at improving and upgrading urban areas, which may include infill as one of its strategies, but also encompasses aspects like infrastructure improvements, housing rehabilitation, and community services enhancement.

Reconstruction often refers to the rebuilding of structures or areas that have been significantly damaged or destroyed, focusing more on restoring existing conditions rather than developing new spaces.

Gentrification describes the process where a neighborhood undergoes a transformation through an influx of wealthier residents and businesses, which typically leads to rising property values and the displacement of lower-income residents. While gentrification can be a consequence of infill development, it is not synonymous with the process of filling in empty spaces.