Omkareshwar a Hindu temple dedicated to God Shiva. It is one of the 12 revered Jyotirlinga shrines of Shiva. It is on an island called Mandhata or Shivapuri in the Narmada river; the shape of the island is said to be like the Hindu ॐ symbol.
There are two main temples of Lord Shiva here, one to Omkareshwar (whose name means “Lord of Omkaara or the Lord of the Om Sound”) located in the island and one to Amareshwar (whose name means “Immortal lord” or “lord of the Immortals or Devas”) located on the south bank of Narmada River on the mainland. As per the sloka on dwadash jyotirligam, Mamleshwar the other name of Amareshwar is the jyotirling, nonetheless, many consider both Omkareshwar and Mamleshwar equally sacred and representative of jyotirling at this sacred place.