Although San Francisco has its fair share of iconic buildings—Transamerica Pyramid and 555 California are synonymous with the city—one high-rise has garnered a well-earned cult following: 130 Bush, a super-slender structure tucked away in the Financial District.

It’s easy to miss the pin-thin tower. Blocked from a clear view on Market Street by One Bush, a spectacular midcentury behemoth in its own right, passersby must veer up the start of Bush Street in order to see and appreciate 130 Bush in all its trim glory.

Furthermore, due to its height, tight positioning between several buildings, and lack of proper signage, this building is woefully underexposed on Instagram. Here’s why that needs to change.

Christened the Heineman building, 130 Bush started life in 1910 as a necktie, belt, and suspender factory. In fact, it was one of the first buildings in the area, built four years after the great earthquake.

G.A. Applegarth, a noted local architect, was commissioned by H.M. Heineman to create the factory in a space not much larger than an average house lot. The lot measures a petite 20 feet by 80 feet deep. Applegrath managed to build a 10-story factory in the slim space—and a gorgeous one at that.

“Building is much like toothpick,” read the headline of a 1909 issue of San Francisco Call reporting the building’s groundbreaking.

L.G. Segedin’s 1996 book 130 Bush Street: An Illustrated Story About Four Buildings and a Monument in San Francisco (egregiously out of print, but available in limited supply on Amazon), provides a detailed history of the svelte structure:

The tall slender building was designed with a Gothic facade and faced with glazed terra cotta tiles. Each story was accentuated with hammered copper panels. Bowed windows with prisms directed the sunlight into the narrow spaces. The ten stories were equipped with over 100 interior ceiling light fixtures hung in oral reflectors. It was the brightest, busiest building in the neighborhood of garment manufactures and wholesalers.

During that time, horse-drawn wagons and motor trucks congested the street throughout the day, hauling items such as lace, ribbons, velvets, silks, flannels, cottons, linens, underwear, and hosiery to the factory.

As the city grew and demand for office space increased in the downtown area, manufacturers moved to less populated parts of the city, like South of Market and Dogpatch. Almost 20 years after its birth, 130 Bush stopped manufacturing operations and turned into office spaces.

During that time, two taller and brawnier buildings rose up next to the lanky structure—the zaftig, 14-story Adam Grant Building and the Gothic 28-story Shell Building:

“With giants on both side, 130 Bush Street stood out more than ever,” notes Segedin. “The bowed windows of the narrow building appeared to result from being squeezed by its neighbors.”

The embossed line the building creates between the Art Deco Shell building to the east and the brick Adam Grant building to the west further highlights its appeal.

Years later, the Iron Duke restaurant opened at 130 Bush in 1956. It featured a kitchen in the basement, an informal dining space at street level, and a formal dining room on the second floor.

One year later, demolition started on the triangle of land between Bush and Market for the aforementioned Crown Zellerbach Corporation’s midcentury at One Bush. During construction, spectators were finally able to see the pinched building at 130 Bush, and articles about the narrow beauty began to appear in local newspapers.

Unfortunately, the nearby construction meant a lot of racket.

“As construction continued on the Crown Zellerbach Building, 130 Bush’s popularity diminished,” says Segedin. “The noise was so great that the Iron Duke restaurant was forced to close during construction.”

Today the building houses Sushi Umi, a Japanese eatery popular with worker drones for quick lunches. Today’s tenants range from a criminal attorney’s office to a nail spa.

The Heineman building, as well as Adam Grant and the Shell Building, are all on San Francisco’s preservation list as category type one buildings for their architectural qualities and impact on the city.

Over a century later, in this era of glass wall overload, the Apple UFO, and Darth Vader-like tech headquarters, the Heineman building’s pin-thin charm continues to excite architecture geeks and passersby who take the time to spot it among its hefty neighbors.