It’s where people from over 82 countries — including Russia, the Philippines, Japan and Mexico — were met with strict enforcement of immigration laws. Chinese immigrants made up the majority of newcomers seeking entry at Angel Island.

The facility operated for three decades, from 1910 to 1940, and shut down after a fire. What remains has been restored as a museum.

Joe Chan, a 76-year-old volunteer docent for the museum, made the rigorous hike this morning without breaking a sweat. A group of a dozen visitors join him for a tour.

He starts his tour in front of a large bronze bell. It marks where cargo ships carrying immigrant passengers used to dock.

“The U.S. Immigration Station was open on Angel Island from 1910 until 1940 primarily to enforce the Chinese Exclusion Act of 1882," Chan explains. “It was the first law designed specifically to keep a group of people from freely entering the United States.”

California is now a "sanctuary state" but back in the 19th Century, the state pushed hard for the passage of the Chinese Exclusion Act.

The Golden State even had its own laws targeting Chinese people. The immigrant laborers had to pay higher taxes, couldn’t own land or attend public schools.

On the tour, Chan leads us to a pair of concrete steps that immigrants climbed after they got off the ship.

It’s where they were separated according to race, gender and age. There were different entrances into the facility for European immigrants and non-Europeans.

“So inside the admin building, they're greeted by an American doctor wearing a long white lab coat. And the doctor says to each group in turn ‘Strip! Take off [your] clothes,'" Joe says.

He tells us immigrants then had to give a stool sample and undergo a humiliating medical examination.

“If you were sick, you had to pay for your own medical treatment. If you couldn't afford it you were deported. If you are not sick you continued on through the maze of the administration building and up the covered stairway and into the barracks where you'd wait for your interrogation.”

Compared to Ellis Island, where immigrants were processed and let through in two to three hours, Chinese immigrants at Angel Island were detained for an average stay of three weeks to six months. A few were kept nearly two years.

The lengthy stay was due to the fact that Chinese immigrants had to explain why they were exempt from the Chinese Exclusion Act. There were some exceptions to the law, which allowed merchants, clergy, diplomats, teachers, students or children of U.S. citizens to enter.

And then there was a loophole made possible because of a natural disaster.

The 1906 earthquake and fire destroyed San Francisco's City Hall, which held countless birth certificates.

“And some smart Chinese man stands up proudly and says, ‘I was born right here. And oh by the way I have five sons in China I want to bring over here because that was allowed under the Exclusion Act and you guys can't prove otherwise because I lost my birth certificate in the Great Fire of 1906,’” Chan says.

So many Chinese labors already here — from the Gold Rush era and the construction of the transcontinental railroad — seized the opportunity by claiming they were U.S. citizens with children back in China.

Hopeful immigrants paid large sums of money to pretend they were those children: called “paper sons” or “paper daughters.”

While sailing across the Pacific they would memorize facts about their new identities because once they got to Angel Island they would have to answer hundreds of questions.

Immigration officials asked minute details to try and weed out who was telling the truth and who wasn’t.

Sponsoring relatives living in the U.S. were brought in for grueling interrogations as well. Answers had to match up. Otherwise, immigrants risked deportation.

The original interrogation room no longer stands, but a granite table engraved with immigrant records recalls what the interrogations were like. Chan stands next to it and fires off a round of questions asked of Chinese immigrants:

“What's the name of your village? Where is it located? There's a wall around your village? What's it made out of? How many children do they have? How old are they? What are their names? Who lives next door to you on your left? How many pigs do they own?”

Chan knows these were actual questions because he dug up the records from his own father’s interrogation.

Chan points to his father’s name and image etched on the granite table. He was held here in 1926 at the age of 15.

There’s also a document from his mom’s detention on the Island in 1940. She was actually a passport-holding U.S. citizen, born in Detroit, Michigan. She was just returning from a stay in China but held because she was of Chinese descent.

For most of his life, Chan never knew that his parents were detained on the island or that his father was a paper son. It was a family secret.

“For his whole life [my father] was looking over his shoulder for the immigration officials to come knocking on the door. He didn't want me to be implicated in that,” Chan says.

He didn’t learn about his father’s detention until after his father died. Now, Chan wants all Californians to know what happened here.

“This is not a personal story. This is an American story.”

Chan takes the group inside the detention barrack. They are bleak, filled with rows of metal bunk-beds. He says, the larger rooms were meant to house fewer than 60 people, but officials usually crammed 200 inside, worsening the unsanitary living conditions.

“The Immigration Service thought the Chinese were a hardy peasant stock used to sleeping on the ground in China. They didn't need mattresses. But enough complaints arose that mattresses and pillows were soon brought forth,” Chan says.

He adds that detainees also rioted until officials agreed to serve Chinese food inside.

Walking through the various rooms, Chan rattles off accounts about life inside the barracks. He tells the story of one boy who was detained at 12-years-old.

"Since he was tall for his age he was separated from his mother and thrown in with the men," Chan says.

The boy saw his mother twice in a 34 day period through a small window as they passed in the dining hall.

When we reach the end of the tour, Chan pauses and asks us to think how history might be repeating itself.

“Consider what our immigration future should be like. Should we be more exclusive, as we've done in the past trying to keep more people out of this country?” Chan asks. “Or should we be more inclusive and try to allow more people to come to this country? The future is up to us. It's up to all of us.”

The group applauds, but Chan doesn’t give tours for the praise. He just wants to keep this history alive, especially since previous generations were too scared to talk about this dark period.

So he’ll continue to make the tough hike up to the Angel Island’s Immigration Station, persuading people to follow along, and learn what really happened here.