The recognition of low-density urbanisation has been important in documenting how diverse human settlements generated enduring social and economic change. In tropical regions, the key challenges to studying low-density urbanisation have been the difficulty in acquiring past built environment data and integrating the frameworks that illuminate the social behaviours intrinsic to urbanisation. The introduction of lidar mapping and urban science methods has proven revolutionary in our understanding of low-density urbanisation as demonstrated by emerging research on settlements and states in Mesoamerica and Southeast Asia. These studies draw on urban theory to highlight patterns in the built environment associated with profound societal changes including the rise of social institutions, agglomeration effects, and ongoing settlement growth. Here, we present an approach that combines lidar survey and archaeological fieldwork with recent developments in urban science to understand the built environment of Tongatapu; the location of an archaic state whose influence spread across the southwest Pacific Ocean between the thirteenth and nineteenth centuries a.d. Quantitative results show—for the first time—that settlements on a Pacific island were urbanised in a distinct low-density form and that the processes of urbanisation began prior to state development. This study highlights the potential contribution of Pacific landscapes to urban science and the low-density settlement phenomena given the presence of large populations, hierarchical societies, and vast distributions of archaeological built remains on many island groups.

对低密度城市化的认识对于记录多样化的人类住区如何产生持久的社会和经济变革非常重要。在热带地区，研究低密度城市化的主要挑战是难以获取过去的建筑环境数据并整合阐明城市化固有的社会行为的框架。事实证明，激光雷达测绘和城市科学方法的引入对我们对低密度城市化的理解具有革命性意义，对中美洲和东南亚定居点和国家的新兴研究证明了这一点。这些研究利用城市理论来强调与深刻的社会变革相关的建筑环境模式，包括社会制度的兴起、集聚效应和持续的定居点增长。在这里，我们提出了一种将激光雷达调查和考古实地考察与城市科学最新发展相结合的方法，以了解汤加塔布的建筑环境；一个古老国家的所在地，其影响力在公元 13 世纪和 19 世纪之间传播到西南太平洋。定量结果首次表明，太平洋岛屿上的定居点以独特的低密度形式城市化，并且城市化先于国家发展开始。这项研究强调了太平洋景观对城市科学和低密度聚居现象的潜在贡献，因为许多岛屿群上存在大量人口、等级社会和广泛分布的考古建筑遗迹。