There are 12 Jyotir Lingas or enlightening Lingas which are pedestals of any material representing Shiva that sits on a base of circular plate denoting the Shakti or Parvati.
Across India, Shiva blessed different holy spots by establishing his presence in the form of the Linga representing a different manifestation. The linga according to the Shiva Purana ( the book of Shiva ) represents the universe and rids humans of their sins. Please find the stories and my abstract visualizations of the 12 Jyotir Lingas below.
For more – https://en.wikipedia.org/wiki/Jyotirlinga