San Francisco Landmarks
In 1918, the first 139 Golden Triangle light standards were installed along both sides of all the streets, not including alleys, within the area bounded by Market, Powell, Sutter, and Kearny Streets. These same light standards were later added to Mason Street between Market and Sutter, Sutter Street between Kearny and Sansome, and Post Street between Kearny and Montgomery.
The Golden Triangle light standards were not the first electrical lighting in the downtown, but were innovative for their time. In fact, they and the Path of Gold lights represent the most advanced street illumination known to exist in the United States in the early decades of the twentieth century. Both Market Street and the Triangle District were lit with the same type of innovative arc lamps used at the Panama-Pacific Exposition; the fair designed to celebrate the future.
The Golden Triangle lights were equipped with a new type of glass and more powerful lamps that uniformly distributed light, did not cast large shadows, lit the facades of the buildings, helped eliminate harmful ultra-violet rays of light and provided a soft and radiant spread of light.
The glass was amber and was known as San Francisco Golden Carrara glass. As the Journal of Electricity reported in 1919:
The system, unlike many other bright illuminatory systems, is not injurious to the eyes, and the absence of the flaming, piercing, eye-straining arc so common in unscientific illumination, makes it the highest class of street lighting in existence. It is predicted that all improvements in street lighting in the future for years to come will be along the lines of the present system.
The article also reported that the new light standards were more efficient than older models and had a relatively low maintenance cost.
From San Francisco Planning Commission Resolution 16222 adopted on 6 September 2001.