The island was originally a fishing and hunting site for Coastal Miwok Indians, then it was a haven for Spanish explorer Juan Manuel de Ayala.

The station is open to the public as a museum – "a place for reflection and discovery of our shared history as a nation of immigrants".

After the quarters at the docks proved inadequate and unsanitary, a study, authorized in 1904, recommended building a new immigration station on the isolated and nearby Angel Island.

Architect Walter J. Mathews designed the station compound to include an enclosed detention center with an outdoor area and guard tower as well as an administration building, hospital, powerhouse and wharf, which was later known as China Cove.

Construction of the facility involved leveling a former Coast Miwok village site and shell mound, including the interred remains of numerous people.

Chinese immigrants were seen as a threat because they occupied low-wage jobs, and after the economic downturn during the 1870s, Americans experienced serious unemployment problems.

[9] This was significantly different from Ellis Island, which had more relaxed regulation and allowed many immigrants to enter the United States on the day of their arrival.

Some American citizens of Chinese descent participated in immigration fraud as purported parents in return for money, or to help other people of the same ethnicity.

[5] As a result, an extensive and grueling interrogation process was made to weed out the people for making fraudulent claims.

The applicant would then be called before a Board of Special Inquiry, composed of two immigrant inspectors, a stenographer, and, if needed, a translator.

Over the course of a few hours or days, the individual would be grilled with specific questions that only the real applicants would know about, for instance, their family history, location of the village, their homes and so on.

[10] The Immigation Station was in operation for thirty years; however, there were many concerns about sanitation and for the safety of the immigrants at Angel Island.

[9] After the war, the Army decommissioned the military installations, reduced its presence on the island, and left the former Immigration Station to deteriorate.

The buildings were set for demolition but were spared, after Ranger Alexander Weiss discovered Chinese poetry, partially obscured by layers of paint, carved in the wooden walls of the men's barrack in 1970.

Held in these "cages" for weeks, often months, individuals were subjected to rounds of long and stressful interrogations to assess the legitimacy of their immigration applications.

It was difficult to pass the interrogations, and cases were appealed many times over before one could leave the island and enter the United States.

Those that failed these tests often feared the shame of returning to China, and some would commit suicide - either before leaving, or on the voyage back to their homeland.