Coarctation of the aorta (CoA) is present in 0.4% of live births and in 7% of patients with congenital heart disease. While there may be florid presentations of congestive heart failure in the neonatal period, the diagnosis during adulthood is often delayed. We encountered a 20-year-old woman who was discovered to be hypertensive on routine check-up. Following bilateral abnormal renal doppler sonography, MR angiogram revealed a short-segment stenosis of the descending thoracic aorta. Review of her chest radiograph showed a small aortic knuckle. This case highlights an unconventional algorithm in diagnosing aortic coarctation in adulthood.