Abnormalities of the urachus, the vestigial remnant of the allantois, result when the embryonic lumen fails to completely obliterate during fetal development. In adults, urachal abnormalities are most commonly masses, with urachal adenocarcinoma representing the most frequent etiology. Due to the low incidence of urachal masses, guidelines for diagnostic workup and treatment are based off of a limited body of evidence comprised primarily of case reports and retrospective series. We present the case of a fifty-two-year-old woman with a urachal mass. Full radiologic workup consisting of computed tomography, cystoscopy and ultrasonography is included, and the risk factors, treatment and prognosis are discussed.