[citation needed] The hill owes its current name to a semaphore, a windmill-like structure erected in September 1849, for the purpose of signaling to the rest of the city the nature of the ships entering the Golden Gate.

Atop the newly built house, the marine telegraph consisted of a pole with two raisable arms that could form various configurations, each corresponding to a specific meaning: steamer, sailing boat, etc.

On October 18, 1850, the ship Oregon signaled to the hill as it was entering the Golden Gate the news of California's recently acquired statehood.

Exposed rock from this quarrying is still visible from the Filbert Steps and from Broadway, where there was a large landslide on February 27, 2007, that damaged property and forced the evacuation of many residents.

Telegraph Hill retained its name and is now registered as California Historical Landmark #91, with a bronze plaque in the lobby of Coit Tower marking the location of the original signal station.

Telegraph Hill is primarily a residential area, much quieter than adjoining North Beach with its bustling cafés and nightlife.

Today Telegraph Hill is known for supporting a flock of feral parrots, primarily red-masked parakeets (Aratinga erythrogenys), descended from escaped or released pets.

They have established a breeding colony with the support of some residents, as reported in the film The Wild Parrots of Telegraph Hill, and through the help of volunteers with Mickaboo Companion Bird Rescue.

The feeding ban was championed by Mark Bittner, the birds' most outspoken supporter who fed them for years and wrote the book The Wild Parrots of Telegraph Hill.