From Wiki article:
The first sign, featuring the Cities Service logo, was built in 1940, and replaced with the trimark in 1965. In 1979, Governor Edward J. King ordered it turned off as a symbol of energy conservation. Four years later, Citgo attempted to disassemble the weatherbeaten sign, and was surprised to be met with widespread public affection for the sign and protest at its threatened removal. The Boston Landmarks Commission ordered its disassembly postponed while the issue was debated. While never formally given landmark status, it was refurbished and relit by Citgo in 1983 and has remained in operation ever since.
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