Re-Mapping Mediaeval Urbanism in Sri Lanka: A Remote Sensing Re-Assessment of the Urban Form of Polonnaruwa

Bradley Young1*, Prishanta Gunawardhana2, Suranga Gunawardhana3, Paul Penzo-Kajewski1, Rebekah Kurpiel1, and Keir Strickland1

In Sri Lanka, the trajectory of urban development during the Rajarata Period (c. 6th century BCE - 13th century CE) gave rise to vast urban settlements in what is today the North Central Province, exemplified by the UNESCO World Heritage inscribed capitals of Anuradhapura, Sigiriya, and Polonnaruwa. These urban centres feature monumental temple complexes, royal palaces and pleasure gardens, defensive fortifications, sophisticated hydraulic infrastructure, and served as the foci of religious worship and the seat of stately control for the surrounding agrarian populace. Pioneering research by Coningham (1999 & 2006), Coningham and Gunawardhana (2013), and Gunawardhana (2023) has described Anuradhapura as an example of low-density urbanism – comparable in some regards to the urban forms of Angkor or the Maya. However, the urban form of the other Rajarata capitals, Polonnaruwa and Sigiriya, remain less well understood. This paper presents preliminary results from drone mounted LiDAR, in combination with ground-survey and geophysical survey, to re-map the urban landscape of Polonnaruwa. Although the use of LiDAR to investigate tropical urban landscapes is well established in Mesoamerica and Southeast Asia, this project is the first time that drone mounted LiDAR has been utilised in Sri Lanka. Moreover, our preliminary results from Polonnaruwa suggest a significant shift away from the Anuradhapura model, reflecting adaptation and transformation following the urban collapse of Anuradhapura.