The Early Harappan Ravi Phase, named after the nearby Ravi River, lasted from BCE until 2800 BCE. It started when farmers from the mountains gradually moved between their mountain homes and the lowland river valleys, and is related to the Hakra Phase, identified in the Ghaggar-Hakra River Valley to the west, and predates the Kot Diji Phase (2800–2600 BCE, Harappan 2), named after a site in northern Sindh, Pakistan, near Mohenjo-daro. The earliest examples of the Indus script date to the 3rd millennium BCE.