The Indus Valley Civilization, also known as the Harappan Civilization, is an ancient civilization that thrived in the Indus River Valley in present-day Pakistan and northwest India. The exact dates of the civilization have been a topic of debate among archaeologists and historians. There are two widely accepted ranges for the dates of the Indus Valley Civilization - c. 2600 to 1900 BCE and c. 2500 to 1900 BCE.

The c. 2600 to 1900 BCE range is based on archaeological evidence, including radiocarbon dating of artifacts and the stratigraphic analysis of excavated sites. This range is supported by the discovery of several well-preserved cities and settlements, such as Harappa and Mohenjo-daro, which were at their peak during this period. These cities show advanced urban planning, sophisticated drainage systems, and evidence of a flourishing trade network.

On the other hand, the c. 2500 to 1900 BCE range is based on the analysis of pottery styles and ceramic sequences found at various sites. This range suggests that the Indus Valley Civilization began a little later and continued until around 1900 BCE. Some researchers argue that this later start date corresponds with the decline of the Mesopotamian civilization, which had significant trade connections with the Indus Valley.

It is important to note that the dates of ancient civilizations are not always precise due to various factors such as incomplete archaeological evidence and ongoing research. As new discoveries are made and more data is analyzed, our understanding of the timeline of the Indus Valley Civilization may continue to evolve.

In conclusion, both the c. 2600 to 1900 BCE and c. 2500 to 1900 BCE ranges are widely accepted as the possible dates for the Indus Valley Civilization. The exact start and end dates may vary depending on the specific evidence and research interpretation.

C.2600 and 1900 BCE