Describe the Harris-Ullman multiple-nuclei model.

• A. It posits a monocentric city with a single CBD dominating land use.
• B. It argues that a city contains several centers or nuclei around which growth clusters, producing a polycentric urban form.
• C. It predicts land value declines linearly with distance from the central area only.
• D. It assumes land-use is uniform across a single ring.

Answer: (B)

The Harris–Ullman model explains urban form as polycentric, with several centers of activity or nuclei around which growth clusters. As a city expands and transportation improves, different functions—such as commerce, industry, education, or specialized services—locate near multiple centers to reduce travel costs and land rents. This leads to distinct nuclei forming within the urban area, each attracting activities and shaping localized patterns of land use, rather than all activities being concentrated in a single central business district.

This approach contrasts with a monocentric city where a single CBD dominates land use. It also avoids the idea that land value declines in a simple linear way from one center, or that land use is uniform around a single ring. The model helps explain decentralization, the rise of edge cities, and multiple activity hubs along transportation routes that characteristically define many growing metropolitan regions.