Sahasrara — The Thousand-Petaled Lotus
The Sahasrara (thousand-petaled lotus) at the crown of the head is the supreme chakra — the point of union between Kundalini Shakti and Shiva, where individual consciousness dissolves into universal consciousness.
Sahasrara (thousand-petaled) is not a chakra in the ordinary sense but the transcendence of all chakras — the point where the individual energy body opens into infinity. Located above the crown of the head, it is described as a thousand-petaled lotus radiating all colors, containing the Sanskrit alphabet in all its permutations, representing the totality of all possible consciousness. When Kundalini reaches Sahasrara and unites with Shiva, the experience is Nirvikalpa Samadhi — the dissolution of all subject-object structure into pure, undifferentiated consciousness. The Sahasrara is associated with the principle of Shiva (pure awareness without object) — it is beyond all the elements, doshas, tattvas, and all other structures. Returning from Sahasrara Samadhi with the recognition that everyday consciousness is Shiva is the Tantric equivalent of full enlightenment.
When Shakti reaches the crown and unites with Shiva, the separation of the individual from the universal dissolves — this is liberation.
In the tantric texts the Sahasrara is not one chakra among the others but their transcendence — the thousand-petalled lotus at the crown where Kundalini's union with Shiva is experienced as Nirvikalpa Samadhi.
Hatha Yoga Pradipika