In addition to the fairly famous Citgo sign, the Boston area has a second gasoline-based advertisement that’s worthy of note. Over on the Cambridge side of the river, a Shell gas station has its own historic sign:

The Shell sign, in brighter days
[Photo credit: P. Kafasis]

This sign dates back to the 1930s, and was refurbished with LED lights in the early 2010s. However, it recently lost the worst possible letter.