Most of the Rig Vedic Civilizations were situated near the Saraswati river. The Rig Vedic period is known as the early Vedic period, which is estimated to have occurred between 1500 BCE and 1000 BCE. During this time, the Saraswati river was considered the most important river in the region, flowing through the northwest part of the Indian subcontinent. The Rig Vedic texts, which are the oldest known texts of ancient India, mention the Saraswati river as a significant feature of the landscape. It is believed that settlements and cities of the Rig Vedic people were established along the banks of the Saraswati river. However, it is important to note that the Saraswati river is believed to have dried up around 1900 BCE, leading to the decline of the Rig Vedic civilization.