Omkareshwar is on an island called Mandhata or Shivapuri i
There are two main temples of Lord Shiva here. Omkareshwar located in the island and Amareshwar located on the south bank of Narmada River on the mainland. Many consider both Omkareshwar and Amareshwar equally sacred.
As per legend, Vindya, the deity controlling the Vindyachal mountain range was worshipping Shiva to propitiate himself from the sins committed. He created a sacred geometrical diagram and a Lingam made of sand and clay. Shiva was pleased and appeared in two forms--- Omkareshwar and Amareswara. Since the mud mound appeared in the form of Om, the island came to be known as Omkareswar. There is a shrine for Parvati and five-faced Ganapathi in the temple.
Another story relates to Mandhata and his son's penance. King Mandhata of Ikshvaku clan worshipped Lord Shiva here till the Lord manifested himself as a Jyotirlinga. Some scholars also narrate the story about Mandhata's sons-Ambarish and Muchukunda, who had practised severe penance and austerities here and pleased Lord Shiva. Because of this the mountain is named Mandhata.
The third story says that once upon a time there was a great war between Devas and Danavas, in which Danavas won. This was a major setback for Devas and hence Devas prayed to Lord Shiva. Pleased with their prayer, Lord Shiva emerged in the form of Omkareshwar Jyotirlinga and defeated Danavas.
Omkareshwar is said to be the place where Sri Adi Sankara met his Guru Govindapada in a cave. This cave can be found even today just below the Shiva temple where an image of Adi Shankara has been installed.
Another legend is the story of the Vindhya mountain, who was once provoked by sage Narada, who teased it that Mount Meru was more important. Vindhya was determined to prove Narada wrong and started observing strict penance with the aim of pleasing Lord Shiva.Lord Shiva was greatly pleased by the devotion of Vindhya and granted him his wish of being greater than Meru. The lingam that was worshipped by Vindhya was split into two on the request of the Gods and sages.
Omkareshwara Temple is located at a distance of about 12 miles from Mortakka in Madhya Pradesh. A special feature of the location of Omkareshwar Temple is that the river Narmada branches into two and forms an island Mandhata or Shivapuri in the center. The shape of the island resembles that of the visual representation of the Omkara sound, Om.
The Omkareshwar Temple is built in the Nagara style and is characterized by a lofty shikhara. There are also shrines to Annapurna and Ganesha here. Before entering the temple one has to pass through two rooms. The Omkareshwar is not affixed to the ground but is naturally installed there. There is always water around it. The significance of this linga is that the linga is not situated below the cupola. The idol of Lord Shiva is situated on the top of the temple. The temple can be reached by ferry from the banks of the river.
Lord Shiva made two parts of the lings. One half being Omkareshwara and the other Amaleshwara or Amareshwar.
Numerous recluses like Agastya have performed serious penance at Omkar-Amaleshwaram JyotirLingam.
In 1063 AD, Parmar King Udayaditya introduced four stone engravings with four Sanskrit Stotras and devoted them to the Amaleshwar Temple. Pushpadanta's "Shiva Mahima Stotra" can likewise be seen as a stone engraving.
Omkareshwar has two lofty hills and it's divided by a valley, creating a shape of the sacred Hindu symbol 'OM' from above.
It is said that Lord Shiva visits here to sleep or 'Shayan' every night and so 'Shayan Arti' is performed here.
It is believed that worshipping Omkareshwar is synonymous to visiting and worshipping Kedarnath and Panch Kedars.
Archaeologists have guessed that the Jyothirlinga inside the temple was originally located in a small ancient temple where a large holy place was built by and by.
When the Mughal emperors and Mahmud Gazni attacked several Hindu temples in the 11th century, Omkareshwar temple was one of them that luckily escaped the attack and became one of the most popular holy places for Hindu pilgrims.
Walk up 287 steps to the 11th century temple of Gaudi Somnath from where you can go down the hill to the northern part of the island. Explore the elegant sculpted Siddhanatha Temple in Omkareshwar, which is embellished with wonderful elephant carvings around its base
.An annual fair is held at Mandhata in the first fortnight of Karthik which is attended by thousands of devotees.