The pelvis of each kidney is drained by a ureter, a muscular tube extending from the hilum to the posterior portion of the urinary bladder.

Ureters are smooth muscle structures, and urine is passed through each ureter by peristalsis. Drop by drop, urine passes into the bladder. Ureters are about 15 to 18 inches in length and about 1/5 inch in diameter.

The kidney drains through the ureter and into the bladder.