Turns out there are hundreds of “sanctuary cities” for undocumented immigrants – do you live in one?

With Donald Trump set to take over the presidency in 2017, immigration reform is bound to occur. Yet, there are many sanctuary cities in the U.S. that aim to protect illegal and undocumented immigrants. The mayors of major American cities like New York, Los Angeles, and Chicago have all come out to say, after Trump’s election, that they will not change their status on immigration and will remain sanctuaries.

So, what’s the deal with these controversial sanctuary cities? And do you live in one?

Despite Trump’s own wife being an immigrant, the president-elect has taken a hard and racist stance on immigration. But sanctuary cities have actually been around a lot longer than Trump’s political career. CNN reported in 2015 that San Francisco’s sanctuary law started back in 1989 and explained how sanctuary cities came to be:

"The sanctuary movement is said to have grown out of efforts by churches in the 1980s to provide sanctuary to Central Americans fleeing violence at home amid reluctance by the federal government to grant them refugee status," CNN wrote.

Murray: Seattle will remain a sanctuary city for immigrants even if we lose millions in fed dollars, bc it's right thing to do. pic.twitter.com/RcdAhQwXax

— Erica C. Barnett (@ericacbarnett) November 9, 2016

Nowadays, many sanctuary cities have been at odds with the U.S. Immigration and Customs Enforcement (ICE) agency, which was created in 2003. On its website, ICE says its purpose is to enforce “federal laws governing border control, customs, trade, and immigration to promote homeland security and public safety.”

But sanctuary cities sometimes find that ICE’s method of protecting the country go against their cities’ well-being. In 2014, Immigration Impact — a project of the American Immigration Council — wrote that 250 counties had stopped honoring detainer requests from ICE because of “constitutional, public safety, and economic concerns.”

Rahm Emanuel: Chicago "always will be a sanctuary city." pic.twitter.com/V2HFK1lNqm

— Fox News (@FoxNews) November 14, 2016

As explained by the American Civil Liberties Union (ACLU), these detainer requests come from ICE and ask that immigrants who have come in contact with police be held in jail for an additional 48 hours so ICE has extra time to decide if the individual should be placed in the federal deportation system.

ACLU and Immigration Impact say these detainer requests are not mandatory, legally speaking — and so certain states and counties have policies not to uphold these requests.

Sanctuary cities — particularly San Francisco — have come under fire recently though by Trump and others after Kathryn Steinle was murdered in July 2015 by Juan Francisco Lopez-Sanchez. Lopez-Sanchez is an illegal immigrant who had been deported back to his native Mexico five times before. The San Francisco Sheriff’s Department had released Lopez-Sanchez in April 2015 after drug charges, even though ICE had submitted a detainer request, since it’s the city’s policy not to hold immigrants who don’t have violent records.

Obviously sanctuary cities are a complicated issue, but can be a refuge for illegal immigrants and their families who do not commit any major or violent crimes. But it’s further complicated by the fact that TeenVogue noted that sanctuary cities aren’t necessarily officially recognized (so Trump can’t technically abolish them) and each has its own policies. For example, Los Angeles’ stance, according to the Los Angeles Times, is:

"L.A. no longer turns over people arrested for low-level crimes to federal agents for deportation and moved away from honoring federal requests to detain inmates who might be deportable past their jail terms."

TeenVogue also referred to the Immigrant Legal Resource Center’s list of city or county detainer policies, which “limit the compliance of local law enforcement with ICE holds to some degree.” While that doesn’t mean the cities or counties won’t work with ICE, it means they all have some sort of restrictions when it comes to complying with ICE’s detainer policies.

NPR writes that there are nearly 300 sanctuary cities and counties in America, including Baltimore, Boston, Chicago, Las Vegas, New Orleans, Philadelphia, and Seattle. To find out if you live in a sanctuary city, check out Immigrant Legal Resource Center’s list. You can also read up on your city or county’s policies and get a better understanding of immigration enforcement, so you’re informed when president-elect Trump takes office in January 2017.