Donald Trump and Hillary Clinton arrived Saturday, along with a spate of other candidates, while Jeb Bush stopped by on Friday. It's a must-visit destination for anyone -- whether they're a real estate magnate or a former secretary of state -- who wants to be president.
Scroll down for a look at what's happening. All times are Eastern.
There's only one thing left to do after a summer day of subsisting on fried Oreos, turkey legs and pork chop on a stick: Get your cholesterol checked. Fortunately, the folks at the fair thought of that already, reports CNN's Betsy Klein:
Massive crowd turns out for Sanders
Trump and Clinton may have drawn large crowds, but according to CNN's Eric Bradner, Vermont Independent Sen. Bernie Sanders drew the largest crowds of the afternoon, at least so far.
Sanders appeared on the Register's Soapbox, where he presented his progressive platform: shifting wealth from the top 1% of earners to the lower and middle classes, equal pay for women and greater benefits for new parents.
"When a woman has a baby in this country, regardless of her income, she should be able to spend three months with that baby, loving that baby, getting to know that baby. That's a family value," he said.
Despite efforts by the Affordable Care Act to make health care more accessible, Sanders said more than 30 million Americans still aren't insured.
"Our job is to make sure that we join the rest of the world in guaranteeing health care to every man, woman and child as a right of citizenship," he said.
As Sanders spoke, a helicopter flew overhead -- Trump's helicopter, as it happened.
"I knew I forgot something today. I just left the helicopter at home," Sanders deadpanned, to laughter. "I apologize. I think we have a rental Dodge car. We'll have all the parents give kids rides in the Dodge."
Trump makes rock star-like appearance
The Donald arrived to the fair shortly after 1 p.m. in grand fashion, landing in his private helicopter that has "TRUMP" emblazoned on its side. His helicopter gave children free rides, and although the fair wouldn't allow him to take off on fairgrounds, he used a nearby parking lot to make the flights.
After disembarking off the helicopter, Trump spoke with reporters for several minutes, touching upon a variety of subjects. When asked by CNN's Jeremy Diamond if he would be willing to spend $1 billion of his own money on his campaign, Trump shrugged.
"It's irrelevant," he said when asked how much he has spent so far on his campaign. "I make $400 million a year, so what difference does it make? What I want to do is make the country great."
As he has said often during his campaign, Trump told reporters he doesn't need lobbyists' money because he is wealthy enough to finance his own campaign, drawing a contrast between him and Bush. He said the former Florida governor was a "puppet" because he relies on the fundraising, the second straight day in which Trump has described Bush in that manner.
Trump also said he would reveal a five-to-six page position paper on his immigration policy proposal. On Friday, Trump said he was planning on unveiling his plans
for both immigration and overhauling the U.S. tax code next month, but said at the fair he would discuss the immigration plan on Sunday during an appearance on NBC's "Meet the Press."
After the press avail, Trump entered the fairgrounds, where he was mobbed by hundreds of fair-goers who wanted to shake his hand or just snap a photo of him. He was closely guarded by a half-dozen security guards and another 10 police officers, a mix of local cops and state troopers.
As he shook hands, the sound of his helicopter could be heard overhead, whirring in the bright blue sky.
Bill Leffelhardt, an independent from Sheffield, Iowa, who said he's caucused for Republicans in the past, described Trump's candidacy as a "political tsunami."
"Look what this is. I mean, this is August. This is unbelievable," he told Diamond.
"Nobody can handle the Donald Trump tsunami. Nobody," he added. "If he just tones down a few things, gets his people in place, brings the women in, it's a done deal."
Trump spent about an hour at the fair, eating part of a pork chop at the Iowa Pork Producers' tent.
"That's the real deal," Trump exclaimed as he held up the pork chop for the media to take photos.
After a few bites, Trump put it back in a takeaway box of pork chops he planned to take back to New York with him.
Diamond later asked Trump what he accomplished Saturday.
"Everything," Trump said.
Clinton responds to latest controversy over her email
The Democratic front-runner met a cow before meeting the press at the fair, CNN's Eric Bradner reports. She was introduced by former Iowa Sen. Tom Harkin, who endorsed Clinton earlier this week
She was immediately asked about the swirling controversy over her use of a private email server while she led the State Department. On Friday night, Clinton joked about why she loves the social media app Snapchat
, saying, "those messages disappear all by themselves."
But Clinton dismissed any suggestion that she was taking the controversy too lightly when asked by CNN's Jeff Zeleny on Saturday.
"I never sent classified material on my email and I never received any that was marked classified," Clinton said, repeating a claim she's made repeatedly. "I'm going to let whatever this inquiry is to go forward and we'll await the outcome of it."
Moreover, Clinton said, the issue isn't brought up when she meets Americans on the campaign trail.
"It is never raised in my town halls," she said.
She was also asked about comments made by Bush, who earlier this week blamed Clinton and President Barack Obama
for withdrawing troops too quickly from Iraq. Clinton said she found it "somewhat curious" that Bush is defending his brother's record in Iraq.
"If he's going to do that, he should present the entire picture, including the agreement that Bush made with the Maliki government in Iraq that set the end of 2012 as the date to withdraw American troops," Clinton said.
Not surprisingly, Clinton was swarmed by media everywhere she went at the fair.
Trump pounced when asked later in the afternoon about Clinton's assertion that the email controversy was pure partisanship, telling Zeleny, "It's a criminal problem." He added that it was impossible for Republicans to overreach on the issue.
"It was a terrible thing she did. It was a very foolish thing," Trump said. "There was no reason to do it. She's got a big problem."
Sanders, however, declined to attack his primary Democratic rival when asked if the email issue was a legitimate concern for Democrats.
"Speak to Hillary about that," Sanders told Zeleny.
He was far more talkative when asked whether he would welcome Vice President Joe Biden into the race.
"I've known Joe Biden for decades," Sanders said. "He is a very decent guy. He is a friend of mine. If he gets in that's great. If he doesn't get in, that's great."
Livestock in the Hawkeye State
There are lots of opportunities to check out pigs, goats and even a butter cow at the Iowa State Fair. At this year's fair, there is a "Pig Place," "Animal Learning Center," "Sheep Stop," "Horse Haven," "Cattle Corner" and more, according to the fair's official website.
CNN's Betsy Klein stumbled upon a cattle crossing on her way to see Clinton at the fair.
CNN's Jeremy Diamond and Sara Murray hung out with some pigs on Friday.
A foot-long corndog?
The Iowa State Fair has been known for its odd food offerings, and this year has been no different. Dispatches from CNN Politics reporters show the unique variety of the Iowa State Fair diet:
Meet Trump's man in Iowa
CNN's Jeremy Diamond speaks to the man
leading Trump's operation in Iowa to examine how the real estate mogul is redefining what it means to campaign at the Iowa State Fair.
Veteran Iowa political operative Chuck Laudner previously carried Rick Santorum to surprising success at the 2012 Iowa caucus -- but don't expect Trump to hop into Laudner's famed pickup truck, nicknamed the "Chuck Truck."
"No, no, not gonna happen," Laudner said in an interview Friday at the fair.
Trump will descend onto Iowa from the sky from one of his private aircrafts before setting aside some time to give kids a lift in his helicopter.
Jeb cheats on Paleo diet
(Friday, 7:51 p.m.)
Bush shared his secret
for making the "Paleo" diet work: cheating.
"The only way to be on the diet is to cheat," he told one reporter, according to CNN's Ashley Killough. In more than four hours at the fair, he had a fried Snickers bar, a beer and a fried potato chip.
He also had a pork chop on a stick, but meat is a key staple for anyone on the so-called "caveman diet" that only allows meat, fish, vegetables, fruits and most nuts.
Bush's marked success on the diet has become a key topic of conversation for voters and journalists who cover him, in part because of how rarely public figures openly discuss their eating habits.
Since starting the diet after Thanksgiving of last year, Bush has lost at least 40 pounds.
How to survive the Iowa State Fair
(Friday, 6:51 p.m.)
CNN's Chris Moody talked to some veteran Iowa operatives to show how to make it through the fair unscathed
. Among the tips: wear comfortable shoes and stay away from the corn dogs. You can watch the rest of Moody's takeaways below.
Bush pressed over Iraq
(Friday, 11:55 a.m.)
CNN's Tal Kopan and Ashley Killough report: Friday's big news at the fair came when Bush stood up on the soapbox, where every candidate is invited to take questions from the audience. This is where Mitt Romney famously declared that "corporations are people"
This year, Bush got grief
over the Iraq War launched by his brother. One of the fair-goers asked Bush whether he was being advised by Paul Wolfowitz, George W. Bush's deputy secretary of defense and the architect of his Iraq War policy.
Bush said Wolfowitz was providing some advice, but he insisted he was his "own person" and pointed the audience to the foreign policy speech he gave earlier this week
in California, saying that was where he articulated his policies if spectators wanted more information.
ICYMI: The candidates who came before
Former Arkansas Gov. Mike Huckabee, former Sen. Jim Webb, former Maryland Gov. Martin O'Malley and former Sen. Rick Santorum visited the fair earlier this week, meeting with Iowa voters and taking turns flipping pork chops and talking about their campaign on the soapbox.