Anirīṇa Tīrtha lies to the south of the river Sarasvatī, within the sacred land of Samantapañcaka (Kurukshetra). It was chosen as the place for the gadāyuddha (mace fight) between Bhīmasena and Duryodhana. This was on the day after Duryodhana came out of the Dvaipāyana lake. The mace fight was the last single combat of the Kurukshetra war.

The place chosen

The Mahābhārata says that Anirīṇa lies south of the Sarasvatī in the sacred land of Samantapañcaka, also called Kurukshetra. The Pāṇḍavas and Duryodhana left the Dvaipāyana lake, together with Balarāma and the others who had come to watch. They moved to a place for the fight and went on to Anirīṇa. They turned their faces to the west and chose this holy tīrtha as the site.

The mace fight

Bhīma and Duryodhana were two of the greatest mace fighters of their time. Both were students of Balarāma. Their gadāyuddha was fought here and lasted the better part of a day. So Anirīṇa became the place of the last act of the Kurukshetra war.

Sources

Mahābhārata, Śalya Parva, Chapter 55.