There are 72,000 nadis (channels) through which vital air flows and shows its activity (Hatha Yoga Pradipika IV.18). These nadis or nerves are said to originate from ‘kanda’ or ‘kunda’, which is a triangular structure at the base of the spine. Kunda literally means a cavity or a pit. Fourteen main nadis, starting from kanda, have been mentioned. Shankhini nadi is one of them. It is said to be situated between two other nadis, namely, Gandhari and Saraswati. From kunda it is said to go to the left ear and then further upward to the head.
Shankhini Nadi is also referred to in Sat Chakra Nirupana of Purnananda in the description of kundalini power and six lotuses. In the commentary of the first verse, it is said that one branch of Shankhini emerges from the hollow of the throat, goes obliquely to the forehead and is then united with and twisted around citrine nadi, which in inside vajra nadi, running within sushumna nadi. Next it passes to the head. Arthur Avalon explains that Shankhini nadi starts from kanda, reaches the throat, then branches into two; one branch goes to the left ear and the other to the top of the head.
In Satchakranirupana, it is said that a thousand-petal lotus is situated above the Shankhini Nadi.