The navicular fossa is a short dilated portion of (the spongy (or cavernous or penile) portion of) the male urethra within the glans penis just proximal to the external urethral meatus.

[citation needed] It is one of three dilations of the male urethra (the other two occurring at the prostate, and the bulb of penis).

[1] The wall of the navicular fossa is the only part of the urethra that is lined with stratified squamous epithelium (instead of the transitional epithelium that is typical for the urinary tract).

[1] During development, the glans of the penis is initially solid but cannulates to give rise to the navicular fossa.

[citation needed] This article incorporates text in the public domain from page 1235 of the 20th edition of Gray's Anatomy (1918)