Kundalini or snake energy is associated with worldly body but is not based upon it and neither it can be found in the subtle body. As a matter of fact, Kundalini energy resides in the causal body where notions of nation, age and circumstances become obsolete.
How Kundalini philosophy is related to supreme consciousness? Lying in an inanimate state, this snake energy gets uplifted through rationale. Then this dormant consciousness along with world consciousness goes through various situations to become one and reaches the highest level. The highest consciousness or lord Shiva's state which is believed to be located in the crown of the head. This section is called "The Hiranyangarbha" in the vedas. The main gland is located in the cap of the head is called the pituitary gland.
Direct below this highest consciousness is another centre which is called "The Hiered eye" or "Agya Chakra". It is related to the pineal gland and is the main centre of transcendentalism. It is located at the hrid eye brow centre. Agya chakra is very important as both Sahastra, located in the supreme consciousness and Muladhar (the unconscious mid located below the spine) are related to the sixth sense. That is why, this energy is the link between the unconscious and the conscious.
Kundalini Yoga is neither unworldly nor irrational. It is based on the physical body. For a Kundalini yogi the presence of highest probabilities indicates supreme consciousness. (For growth, this physical body's entities gradually changes into delicate matter like experience, meditation, reason, memory and doubt) The growth of this transcendental or veteran energy is the main stage in human progress.