The origin of transverse arterial branches that contribute to the arterial supply of the odontoid process (dens axis) is not clear. Dissections were performed on 20 injected fetal and adult human cranio-cervical junctions to demonstrate the origin of the arteries that contribute feeding branches to the arteries supplying the neck of the odontoid process. At its termination near the anterior arch of the atlas, the ascending pharyngeal artery gave off transverse branches that anastomosed with the anterior ascending arteries to the odontoid process. It also gave off a branch that traversed the hypoglossal canal and anastomosed with the posterior ascending artery. A small branch linked the posterior ascending artery to the first transverse branch. This investigation complements previous work on the arterial supply to the odontoid process.