The cervical nerves are the spinal nerves from the cervical vertebrae.
Although there are seven cervical vertebrae (C1-C7), there are eight cervical nerves (C1-C8). All cervical nerves except C8 emerge above their corresponding vertebrae, while the C8 nerve emerges below the C7 vertebra. (In the other portions of the spine, the nerve emerges below the vertebra with the same name.)
Dorsal (posterior) distribution includes the suboccipital (C1), greater occipital (C2) and third occipital (C3).
Ventral (anterior) distribution includes the cervical plexus (C1-C4) and brachial plexus (C5-T1).