Public open space is an essential structuring landscape element and is a pivotal point for the civic social system in a city. Unplanned urbanization and densification are often deemed responsible for the disappearance of public open spaces in Dhaka. Since 1960, as one of the fastest-growing megacities, Dhaka faces continuous destruction of open spaces that includes seven vulnerabilities: water, riparian areas, parks, vacant lands, green areas, greenways, and ecological reserves. To ensure sustainable growth along with proper functioning of ecosystems, foster social cohesion and public health, there is an urgent need to assess shifts in Dhaka's landscape - by re-evaluating the interaction between Dhaka's Public space and the urbanization of its natural landscape. Therefore, this article explores historical avenues of Dhaka's natural-urban metamorphosis through urban mapping and cartographic exploration to understand the transformation of public open spaces over time. This way, the aim is to identify future potentials for preserving nature and strengthening the role of public open space and its manifold uses through unfolding the hidden layers of history.