The common iliac arteries are major blood vessels that branch off from the abdominal aorta. They are located in the lower abdomen and each artery divides into two smaller branches: the internal iliac artery and the external iliac artery. These arteries supply blood to the pelvis, lower limbs, and reproductive organs. The right and left common iliac arteries are symmetrical and run parallel to each other. They typically begin at the level of the fourth lumbar vertebra and extend downwards, playing a crucial role in the circulatory system by delivering oxygen-rich blood to various regions of the body.