Cobb Point Bar Light, also known as Cobb Island Bar Light, was a screw-pile lighthouse in Maryland’s Potomac River that marked the narrow, difficult entrance channel to the Wicomico River. Sought for years as river traffic increased in the late 1800s, it was funded by Congress in 1889, prefabricated at Lazaretto Depot, and assembled on site in just over a month. Entering service on Christmas Day 1889 with a fourth-order Fresnel lens, it became part of a wider network of Potomac lights serving larger ships and steamship lines. Its service ended after a fire in 1939 heavily damaged it, and it was replaced by a beacon the next year.