Most of the mature Harappan sites in the region of Cholistan had been abandoned during

The Mature Harappan phase, characterized by its urban centers and prosperity, is generally dated between 2600 BCE and 1900 BCE [2]. Archaeological evidence indicates that the decline of this civilization began around 1900 BCE, marking the transition to the Late Harappan or 'decadent' phase [3]. In the region of Cholistan, which was a major hub of Harappan settlements, there was a significant shift in settlement patterns during this period. By approximately 1800 BCE, signs of gradual decline became prominent, leading to the abandonment of most mature urban sites in the region. This abandonment is often attributed to environmental factors, such as the drying up of the Hakra river system. While some elements of the civilization persisted in the Late Harappan phase (1900–1300 BCE), the core urban characteristics of the Cholistan sites were largely lost by 1800 BCE.

Sources

1. [1] THEMES IN INDIAN HISTORY PART I, History CLASS XII (NCERT 2025 ed.) > Chapter 1: Bricks, Beads and Bones > Terminologies, Places and Time > p. 1
2. [2] History , class XI (Tamilnadu state board 2024 ed.) > Chapter 1: Early India: From the Beginnings to the Indus Civilisation > Nomenclature, Phases and Chronology > p. 10
3. [3] https://dn790008.ca.archive.org/0/items/ancientindusvalleynewperspectivesjanemcintoshr._586_T/Ancient%20Indus%20Valley%20New%20Perspectives%20%20Jane%20Mcintosh%20R.%20.pdf