Superficial region around the renal medulla

Renal cortex

Explanation:

The renal medulla of a kidney is surrounded by renal cortex. The renal cortex is the granulated layer. It is the renal cortex in which the renal corpuscle (glomerulus and Bowman's capsule) are present. The renal cortex is reddish brown in color. This is due to the fact that most of the renal arteries deliver the blood to the cortex.