The inferior cervical ganglion is one of the three cervical sympathetic ganglia (i.e. of the cervical portion of the sympathetic trunk). It is situated between the base of the transverse process of the last cervical vertebra and the neck of the first rib, on the medial side of the costocervical artery.
It is often united with the first (and sometimes the second) thoracic ganglion to form the cervicothoracic ganglion (stellate ganglion).