Amarkantak is situated in Anuppur district of the state of Madhya Pradesh at an altitude of 1065m at the meeting place of the Vindhya and Satpura mountain ranges amidst sylvan surroundings. It has an average elevation of 1048m.

The mighty Narmada river as well the Son, the Mahanadi, and Arnadoh which is a major tributary of the Godavari all arise in the  Amarkantak plateau. The Narmada river is considered to be 150 million years older than the Ganga.Amarkantak itself is sacred to the Hindus and is deemed to be the gateway to Nirwana.The legends says that Lord Shiva himself blessed Narmada with unique purifying powers. Tradition requires the devout to take a holy dip in the Ganga, perform seven days of prayer on the banks of the river Yamuna and three days of prayer on the banks of the river Saraswati. However, it is believed that the mere sight of the Narmada is enough to purify the devout.

There are about 24 temples in and around Amarkantak, including the ancient temple dedicated to the Goddess Narmada and the temple of Devi Sati. The Trimukhi temple is dedicated to Lord Shiva and is the oldest temple in Amarkantak. It was built by the ruler Karan chendi between the years 1042-1122 AD. The Machendranathh at the Pataleshwar temple are prominent examples of Kalchuri art and expertise.

Source:

http://travel.sulekha.com/travel-to-amarkantak-madhya-pradesh-india_bhopal-travelogue-4188.htm