Despite the wide-spread knowledge among anatomists and surgeons that the azygos vein lies on the right side of the vertebral column, various scientific works have been conducted which suggest the existence of left-sided azygos veins. The displacement of the vessel seems to be related with aging, due to crossover veins and the development of osteophytes on the thoracic vertebrae. The current case report confirms the variation of the azygos vein's course, highlights the awareness of the relatively unusual left-sided location of the azygos vein for the surgeon of the region, and underlines the clinical significance of such knowledge to the modern internist-radiologist, general surgeon and thoracic surgeon, as well.