And another 50,000 work there every day.
That all adds up to an enormous and complicated ecosystem.
And amid all this energy is a massive problem that has been building for years - and nobody is talking about.
Well, nobody except a sheriff some 2,000 miles away.
'Drugs pouring out of LAX'
Sheriff Grady Judd of Polk County, Fla., says a large quantity of the drugs that end up in his jurisdiction first entered the country through LAX.
"Over and over on these domestic airlines from LAX, through suitcases drugs were smuggled here," Judd said, as he displayed luggage packed with narcotics at a press conference announcing a drug bust.
Through good police work, his agency cracked a big drug ring - and the bust illustrates a much larger problem.
"On one occasion, on one airline, six suitcases with this drug was smuggled into Orlando," Judd said. "They didn't so much as throw a pair of underwear in the suitcase to act like they were hiding the drugs. You think LAX has got a drug smuggling problem?"
The investigation began four years ago and involved multiple local and federal agencies, resulting in dozens of arrests.
Judd told our sister station KABC-TV one of the lessons he learned from the bust:
"It's so easy not to be caught. We see drugs pouring out of LAX."
"The traffickers know this. This was not a one-off event. This was an everyday event during the operation."
"They use this multi, multi-billion dollar travel industry as their go-to, to move drugs across this country."
He notes his county is just one small jurisdiction and says it's fair to assume similar operations running through LAX are happening all over the country.
And he's right.
A KABC-TV investigation uncovered drug cases across the United States and the globe, all originating out of LAX.
Multiple law enforcement sources say LAX likely is the drug trafficking hub of the world.
So the problem isn't just affecting Los Angeles - but nearly everyone.
Who is responsible for stopping it?
As Sheriff Judd and other law enforcement experts say, it's a shared responsibility.
The TSA, for example, is responsible for screening bags of every passenger that boards a plane - but they aren't looking for drugs.
"Our search authority is very narrow," said Jason Pantages, TSA's security director for LAX. "We search for weapons, incendiaries and explosives and we want to keep those out of bags and off of planes."
LAX is one of the busiest airports in the world - and just looking at originations and destinations, it's the single busiest. They deal with hundreds of thousands of bags and people every day.
Pantages says searching for drugs cannot be part of TSA's job.
"We don't have the ability to do that because we're not law enforcement officials. We're transportation security officers."
"We can't search for criminal activity. It's not within what we're able to do with our search authority."
TSA screens bags brought onboard as carry-ons using an X-ray machine. But when bags are checked in, they are screened just for explosives, not for drugs. If the explosive detective system doesn't detective explosive material, the bag keeps moving.
When TSA agents do detect drugs, the first thing they do is notify law enforcement.
That starts with the LAX police agency, headed by Chief Cecil Rhambo. He notes that his agency has a long list of responsibilities and crimes to monitor, from thefts to assaults to parking violations and, of course, drug trafficking.
But screening bags?
"No," Rhambo says. "Bags are TSA."
The DEA also plays a role in cracking down on drug smuggling at the airport.
"A lot of what they do is investigative," said Matthew Allen, special agent in charge of the DEA in Los Angeles. "A lot of what they do is try to stop the narcotics before they ever actually even make it to LAX."
"So part of the dilemma is if they're not going to look at bags - then who should be doing this?"
"We all have a role to play, right? Screening is not the role of the DEA."
The FBI also plays a role in enforcing drug laws, but only in a limited sense:
When airport employees try to use their credentials to smuggle narcotics past checkpoints.
And when illegal drugs are found on a plane. But only if the doors to the cabin have been shut. While they are open, the plane is still under LAX police jurisdiction.
"It's complicated because this airport is so complicated," says FBI special agent David Gates.
And Homeland Security is another agency that is involved.
"We have approximately 40 special agents that reside there on a daily basis," says John Pasciucco with Homeland Security Investigations.
But those agents are primarily focused on international drug cases, he says. And like the DEA, their focus is on investigations, not screening bags.
That appears to leave a gray area in terms of who is really in charge of stopping drugs from moving through LAX.
Pasciucco argues that the shared responsibility works well and the issue is not one of conflicting or overlapping jurisdictions. It's just about the sheer volume of people, bags and drugs that move through the airport on a daily basis.
That defines the problem. Agencies may be doing their job well but ultimately no one is actually searching all those bags for drugs.
Even when you see trained dogs at the airport - only a few of them are trained to look for drugs. Most are focused on explosives.
No more private airstrips
The cartels figured all this out years ago, and Sheriff Judd says it's made their job easier.
That's why it's rare now to see private drug planes fly into secret landing spots: There's no need.
"We've not seen an airplane, a small airplane, fly into a clandestine strip in decades," Judd says.
"The infrastructure's already in place. The drug dealers don't have to create the infrastructure. It's here."
This is Part 1 of a KABC-TV investigation. Part 2 will air Friday on ABC7.