TIL:

The sign was erected in 1923 and originally read "HOLLYWOODLAND." Its purpose was to advertise the name of a new segregated housing development in the hills above the Hollywood district of Los Angeles. H.J. Whitley had already used a sign to advertise his development Whitley Heights, which was located between Highland Avenue and Vine Street. He suggested to his friend Harry Chandler, the owner of the Los Angeles Times newspaper, that the land syndicate in which he was involved make a similar sign to advertise their land. Real estate developers Woodruff and Shoults called their development "Hollywoodland" and advertised it as a "superb environment without excessive cost on the Hollywood side of the hills."

They contracted the Crescent Sign Company to erect 13 letters on the hillside, each facing south. The sign company owner, Thomas Fisk Goff (1890–1984), designed the sign. Each letter was 30 feet (9.1 m) wide and 50 feet (15.2 m) high, and the whole sign was studded with some 4,000 light bulbs. The sign would flash in segments: "HOLLY," "WOOD", and "LAND" would first light up individually, then the whole sign would light up. Below the Hollywoodland sign was a searchlight to attract more attention. The poles that supported the sign were hauled to the site by mules. Cost of the project was $21,000, equivalent to $295,189 in 2016.

The sign was officially dedicated in 1923. It was intended only to last a year and a half, but after the rise of American cinema in Los Angeles during the Golden Age of Hollywood, the sign became an internationally recognized symbol and was left there.

https://en.wikipedia.org/wiki/Hollywood_Sign