The renal pelvis is the funnel-like dilated area at the center of the kidney. It is proximal to the ureter.The renal pelvis is the point of convergence of two or three major calyces. Each renal papilla is surrounded by a branch of the renal pelvis called a calyx. The renal pelvis is lined with a mucous-membrane layer that is only a few cells thick.
The renal pelvis functions as a funnel for urine flowing to the ureter. It is the location of several kinds of kidney cancer.