To call the pizza of my hometown of Pittsburgh, Pennsylvania, “unappreciated” would be a gross understatement.

By way of example, flip through Daniel Young’s brick-sized 2016 tome Where to Eat Pizza. The book purports to be a compendium of the best pizzerias in cities around the globe. It is a mammoth 576-pages long.

Pittsburgh merits just a single page.

To put that in perspective, Copenhagen, Denmark, gets two and half pages.

This despite the fact that, according to a 2014 data crunch by consultancy Targeting Solutions, Pittsburgh—which by the way has one of the largest Italian-American populations in the United States—also has the highest pizzeria density of any American city except Orlando, Florida. Ten pizza joints per 10,000 people. Residents in certain parts of town would tell you that figure actually seems low; on one three-block stretch of Murray Avenue in the Squirrel Hill neighborhood, you’ll find four pizza joints.

One page in the pizza book, is all Pittsburgh merits? Really?

COPENHAGEN?

What’s worse, even as the Pittsburgh pie is ignored from the outside, it must often be defended from attack from inside, as well.

Last year, in an otherwise fine piece on Eater singing the praises of the french-fry-topped “Pittsburgh salad,” Western Pennsylvania native Shannon Reed could not resist taking a swipe at the city’s pies. “The best place to start the search for bagels and pizza in Pittsburgh,” she claims to have realized after a sojourn in New York City, “was at the airport, where you can buy a ticket to LaGuardia.”

In this sentiment, I think, lies a key to the obscene lack of respect afforded Pittsburgh pizza: It is constantly compared to pies in cities like New York or Chicago.

Which makes sense. There are a lot of people and a lot of media outlets in New York and Chicago. They can familiarize the world with their pizza, and make it the standard against which all other pizza is judged. And admittedly, next to those pizzas, Pittsburgh pizza can seem kinda backwards and brutal.

What’s more, those cities have defined pizza styles. Whereas Pittsburgh pizza has an identity crisis. Last year, over the course of a weekend food conference in Pittsburgh, I asked a random sampling of local food writers and civilians to define what makes Pittsburgh pizza Pittsburghy. Most of them couldn’t say. In fact, many didn’t even think of Pittsburgh as a particularly pizza-centric city. Like oxygen, pizza is so ubiquitous there, they apparently don’t pay attention to it anymore.

So herein I shall attempt to put the Pittsburgh pizza in context and define it, in the hopes of making it less impenetrable to the outsider, and more appreciated by the insider. And perhaps even celebrated for being yes, backwards and brutal.

I should note that what I’m describing, here, is the “classic” Pittsburgh pizza, usually found in joints that have been around for decades. As Pittsburgh’s food scene booms, there are now plenty of newer places serving excellent, wood-fired “authentic Italian” pies with eclectic toppings. But you’ll find those in food-centric cities around the globe. Their pizza is an international, not a local style.

So what makes Pittsburgh pizza different? Firstly:

A Pittsburgh pizza is a vessel for cheese.

You can spot a New York pie by its thin, floppy crust and thin layers of sauce and toppings. Chicago pie has its deep, more rigid crust, and thick sauce.

But Pittsburgh pizza is primarily defined by cheese. Depending on the pizzeria, you will find somewhere between a lot and far too much cheese on your pie. I would call it a “toothsome” amount at minimum, and “an entire cheese shop’s worth” at maximum.

And secondly:

A Pittsburgh pizza’s crust is a gluten-avoider’s nightmare.

The edges of these crusts, the “pizza bones,” can be gigantic. They come out of the oven medium-crisp, super puffed up and chewy. And while the rest of the crust is generally on the thinner side—slices sag beneath the weight of their cheese load—it is also somehow densely doughy.

This, I think, drives much of the disregard for Pittsburgh pizza. Once, after posting a photo of my favorite pie on Twitter, a follower from Virginia replied, “Crust ridiculously thick—no thanks.”

I remember once procuring a slice from the locally renowned shop Mineo’s. It was too hot to pick up, so I tried cutting it with a plastic knife, and discovered that to be an utterly useless endeavor. The knife went easily enough through the cheese, then made a little indentation in the moist top part of the dough underneath, and then I found myself just sawing and sawing, unable to break through the bottom of the crust. I went in there a while ago and noticed they no longer, sensibly, offered patrons plastic knives.

I can’t tell you for sure why these two elements are so common to Pittsburgh pies. But it’s not hard to imagine that a town once full of poor immigrants from places like Southern Italy and Poland—who came to work in the steel mills and suddenly had middle-class incomes and a laborer’s appetite—might want pizzas to be extravagant piles of cheese and dough.

In mid-century Pittsburgh, some pizzerias would stay open into the wee hours, to serve workers who’d just spent a long night shift sweating over white-hot molten metal. These guys probably weren’t looking for a thin, sophisticated Neapolitan number.

Furthermore, you can’t have one of these elements without the other. I don’t know which ingredient came first, but you can’t have a pizza with tons of cheese on it without a crust that can hold it. And you can’t have a crust this thick without nice moist salty toppings to balance it out. The Pittsburgh pie is in your face, but it’s not thoughtless—there’s care put into its construction.

So if most Pittsburgh pizzas share these common characteristics, why do so many Pittsburghers fail to realize local pies have much in common at all?

Chalk it up to the incredible variations you’ll find on these themes. Pittsburgh pies can be completely different from one neighborhood to another and from store to store, sometimes in ways so extreme it’s easy to overlook their shared cheesy, crusty DNA.

On one hand, for instance, you have the infamous Beto’s pizza (on Banksville Road in Beechview). It only serves square slices. You can’t get a whole pie (though they’ll sell you a “tray” of 28 cuts that approximates one).

Each slice is baked with sauce on it, and then the hot slice is taken out of the oven and topped with an unholy amount of cold shredded provolone cheese. So much cheese that sometimes it doesn’t look like there’s any crust underneath. It’s completely obscured by the cheese pile.

This is a slice best eaten with a fork and knife, but I’ve tried lifting one up to take a bite, and the strings of partially-melted cheese stretched down to my elbow. The guy at Beto’s counter told me they go through three thousand pounds of provolone a week.

Beto’s insists their system preserves the flavor of the cheese. And it definitely means it’s not a very greasy pie, since not as much fat renders out. The sauce, meanwhile, is thick, with chunks of tomato—actually, almost a Chicago pizza-style sauce.

Compare this to the pizza produced by another legendary local spot: Vincent’s Pizza Park in Forest Hills. Unlike Beto’s, Vincent’s only serves pies. You can’t get slices there at all. Its sauce isn’t thick and chunky, it’s actually rather thin, and almost an afterthought on the pie—barely detectable.

But the sauce is the only understated thing about Vincent’s pizza. First of all, their pies are enormous. On the wall above the cash register was once a sign that read “THEIR SIZES”—next to a display of standard small, medium and large pizza pans. Beside it, another sign read “VINNIE’S SIZES.” And you could see Vinnie’s Small was most places’ Medium.

Vincent’s uses a blend of both mozzarella and provolone. Again, huge amounts of it. Serious Eats’ Daniel Zeman reviewed the place several years ago, and observed that the cheese “Sits out in a large tub that the people making the pies seem to keep reaching into and adding more until their arms get tired.”

The other toppings are equally extreme. If you order sausage, you won’t get that ground-up spattering of meat common to New York pies. You’ll get sausage chunks nearly the size of ping-pong balls. I have video of Vincent’s Dave Miller making a seven-topping pizza. When it goes into the oven, the toppings are piled about four inches high. It takes long seconds of effort for Miller to extract his giant wooden spatula from beneath the uber-pie.

These pizzas come out of the old gas ovens in a big oval shape. They are, famously, charred coal-black in spots on the outside of the crust. And on a large pie, the outer edge can puff up as thick as an Italian roll.

Thank God for that tall edge, too, because it’s necessary to contain the molten pool of cheese and toppings and especially—again, unlike Beto’s— grease. Cut into a sausage pie from Vincent’s and an incredible volume of vivid orange fat oozes, lava-like, onto the pan. You use the huge edge pieces of crust to soak up the lakes of grease afterwards. It’s delicious.

Now, these pies are the extremes. My personal favorite is actually from a joint called Fiori’s that’s kind of a Vinnie pie that stopped taking steroids — Fiori’s sweet sauce manages to shine through the cheese. But still, there are big variations from neighborhood to neighborhood and pizzeria to pizzeria.

And what I’m saying is that this itself is an inherently Pittsburgh thing. This infinite variation is what makes Pittsburgh pies Pittsburghy.

The geography of Pittsburgh separates neighborhoods from each other in ways you’ll find in few other major metro areas. Rivers, bridges, mountains and tunnels carve the landscape into big, discrete puzzle pieces. There’s no consistent street grid; roads can be steep, winding, narrow, bewildering. So residents, over the decades, turned their neighborhoods into contained little worlds. It’s often said Pittsburgh’s not a city, it’s a collection of villages—and therefore a place where food variations thrived.

My parents have lived just a couple miles away from Beto’s for more than thirty years. Yet until last year, they’d never been inside. They’d never heard of anything like it. I took them, and they were delighted.

So to embrace Pittsburgh pizza is to embrace idiosyncrasy, invention, excess, and weirdness. That is worth celebrating. Copenhagen, your move.