Trayambakeshwara Ji at bank of the river Gautami
Trayambakeshwara Ji in Kashi

There are twelve Jyotirlingas on all India basis and there are twelve important Shiva Lingas in Kashi which represent the above twelve Jyotirlingas. The above deity is worshiped as Trimbakeshwar (Nashik, Maharashtra).
Once the Lord, in the form of Kriti Vaseswara, was sitting with Goddess Uma Devi, when Nandi offered his prayers and said that there are 68 shrines dedicated to Lord Shiva in this holy place. Many idols/Shivling have been brought from many places and installed in Kashi.
A linga by the name of Trimbak from Trisandhyam Tirtha has appeared in the holy city of Kashi, called Trimbakeshwar. By worshiping this deity the devotee will get the respect normally given to the Lord. (In other words, they would be held in high esteem).
Sage Gautama started doing his regular activities and also sowed different types of grains, from which many types of trees and different types of flowers, fruits etc. grew there. Thereafter the various living beings returned to that place and lived there in harmony.
Once the disciples of Sage Gautam went to take water from this Jal Tirtha. At the same time the wives of other sages also came to collect water from there. At Jaltirtha, there was a dispute between the disciples of sage Gautama and the wives of other sages as to who would get the water first.
Meanwhile, Ahilya, the wife of Sage Gautama came there and asked the wives of other sages to let the disciples get the water first as they had come there before them. This made the other sages' wives feel inferior and thought that Ahalya was taking the side of the sage's disciple because of the penance of the water sage Gautama. Therefore, dissatisfied with Ahalya, the wives of the sages instigated their husbands to humiliate sage Gautama.
Thereafter, all the sages started worshiping Lord Ganesha for this purpose. Pleased when Lord Ganesha appeared before him, he asked Lord Ganesha to somehow get Gautam Rishi out of this hermitage. Hearing this, though Lord Ganesha tried to convince the sages that this was unfair, they all remained firm in their wish. Eventually, Lord Ganesha had to grant her wish.
Therefore, Lord Ganesha took the form of a weak cow and began grazing grain in the field of sage Gautama. Seeing a cow grazing in his field, the saint gently tried to remove the cow from his field. During this the cow fell on the ground and died. When all the sages came to know about this they blamed sage Gautama for Gau Hatiya (cow slaughter) and expelled him from the hermitage along with his family.