Proximal Attachment
Trapezius arises by muscular slips from the medial-third of the superior nuchal line of the occipital bone, the external occipital protuberance, the ligamentum nuchae and the tips of the spinous processes and intervening supraspinous ligaments from C7 to T12.  A triangular aponeurosis exists between C6 and T3 corresponding to a hollow seen in the living.  

Distal Attachment
The superior fibers descend to attach to the posterior border of the lateral-third of the clavicle.  The middle fibers pass horizontally to attach to the medial acromial margin and superior lip of the crest of the scapular spine.  The inferior fibers ascend and become aponeurotic as they glide over the smooth triangular surface at the medial end of the scapular spine attaching to a tubercle at its lateral apex.  The occipital attachment is by a fibrous lamina.