Wormian bones, also known as intrasutural bones, are present as an anatomical variation in healthy individuals. However, a higher than the usual incidence can be an important feature of some congenital pathological conditions. In this study we describe a case of an adult cranium with multiple Wormian bones. The cranium was a single sample obtained from an archaeological excavation in Vinitsa, Northeastern Bulgaria, and probably dated in the Chalcolithic. The Chalcolithic is a period of human history connected with discovering and using of copper. Actually, it is a transitional phase between the Neolithic and the Bronze Age. In this case the Wormian bones are mostly large in size and arranged in a mosaic pattern in several cranial regions. The cranium also shows features such as dolichocrany, a moderate platybasia, a notch in the posterior margin of the foramen magnum, hypoplastic and asymmetrical frontal sinuses, underdeveloped mastoid air cells, hyperostosis cranii interna, moderate frontal bossing, a complete metopic suture, a delayed sutural closure, relatively small facial bones, an early loss of teeth, dental caries and hypoplastic enamel defects on two preserved molars. Differential diagnosis indicates that the combination of all these features shows a link with pathological conditions involving dysplasias with prominent membranous bone involvement and an increased bone density such as cleidocranial dysplasia and pyknodysostosis.