The pharynx is the superior expanded part of the alimentary system posterior to the nasal and oral cavities, extending inferiorly past the larynx. The pharynx extends from the cranial base to the inferior border of the cricoid cartilage anteriorly and the inferior border of the C₆ vertebra posteriorly. The pharynx is widest (approximately 5 cm) opposite the hyoid and narrowest (approximately 1.5 cm) at its inferior end, where it is continuous with the esophagus. The flat posterior wall of the pharynx lies against the prevertebral layer of deep cervical fascia.

The interior of pharynx is divided into three parts:
• Nasopharynx: Posterior to the nose and superior to the soft palate
• Oropharynx: Posterior to the mouth
• Laryngopharynx: Posterior to the larynx