The male urethra is about 16 to 22 cm long and 5 to 6 mm wide S-shaped tube. It begins with an inner or internal urethral opening (orifice) in the bladder wall and travels through the prostate, perineum, and corpus spongiosum of the penis to reach its outer or external urethral opening (orifice) in the glans penis. The external opening presents as a vertical slit.