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In 2006, long before Tony B Kim sold licensed superhero apparel for a living, he was just a guy who walked up to the door of San Diego Comic-Con for the first time, bought a ticket and marched right in. Thirteen years later, it's hard to imagine Kim, or anyone else, getting into SDCC without months of planning -- and a prayer to the hotel gods.

The massive event, which started in 1970 as a gathering of about 145 comics fans in a hotel basement, has blown up into one of the world's most highly concentrated -- and highly anticipated -- celebrations of geek culture. Almost 50 years later, it attracts more than 130,000 attendees and consumes not only the San Diego Convention Center, but the nearby Gaslamp Quarter, and seemingly any available green patch or open hotel within reach.

SDCC -- which this year runs from July 18-21 -- spills out everywhere, not unlike geek culture into the mainstream. If you see Chewbacca and Thor walking down the street and overhear snatches of conversation about who should really play Batman, you're in the right spot.

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Tony B Kim

"Nerd culture has merged with and swallowed whole the rest of popular culture, and [Comic-Con] really is part of that," said Rob Salkowitz, author of the book Comic-Con and the Business of Pop Culture: What the World's Wildest Trade Show Can Tell Us About the Future of Entertainment.

When that merge started exactly depends on who you ask. But there's no mistaking that one of the biggest changes to Comic-Con has been the rise in popularity of TV shows and movies that might have once been deemed the sole purview of the nerdy crowd. Consider that from 2013 until now, 10 TV series have spun off from some of the 22 movies in the Marvel Cinematic Universe. Throw in another nine or so for DC. That's a lot of angst and spandex.

In the past decade, properties like the MCU, Game of Thrones, Star Wars and Harry Potter have gripped the zeitgeist like a Devil's Snare. Many people can probably find Mordor on a map and definitely know which Hogwarts house they belong to. Avengers: Endgame is this close to becoming the top-earning movie of all time globally, having already raked in north of $2.7 billion in ticket sales.

"The water cooler talk around the office used to be about who won the big game over the weekend, and now it's about who's going to sit on the Iron Throne," said Kim, that lucky guy who walked right in the Comic-Con door in 2006. Kim runs an apparel company called Hero Within that makes licensed clothing. He also runs the site Crazy 4 Comic Con, a blog with news and updates about SDCC.

The whole thing started on March 21, 1970, at the US Grant Hotel in San Diego. The one-day "minicon," as it was dubbed, was followed that August by a three-day event attended by around 300 guests, including sci-fi powerhouse Ray Bradbury, legendary comic book artist Jack Kirby, and author A.E. van Vogt, whose narrative style influenced Philip K. Dick.

Since those groundbreaking '70s events, the expanding reach of geek culture has meant that fandom, which is absolutely central to Comic-Con, has had to adapt to welcome those drawn by movies and television shows rather than just comics.

And growth rarely comes without growing pains.

Too much to go around?

Artists like Agnes Garbowska, who has illustrated covers for My Little Pony, Transformers and Powerpuff Girls, say they've seen Artists' Alley, a section of the show floor for artists, shrink and grow over the years. Not every Comic-Con attendee she meets realizes when a movie or TV show started off as a comic book. Sometimes, there's some enlightening to do.

"I find myself educating people about comics," Garbowska said. She doesn't mind, though. As someone who used to hide her childhood comic books to avoid being labeled too "weird," she's happy to see a broader acceptance of geekery. She would, though, like to see more cross-promotion between the source material and its adaptations.

Anges Garbowska

For Vault Comics, a publisher founded in 2016, being relatively new to the show is a benefit, said CEO and publisher Damian Wassel. Even when it comes to attracting folks who didn't necessarily come to SDCC for the comics, Vault can still grab their interest, Wassel said.

"It's not hard for me to get somebody who's mostly come for film and TV, news or video game demos to take a moment and look at something new, because that's ultimately what they're there for, to experience new things," he said.

New things, for example, like being surrounded by fans in elaborate costumes. Professional cosplayer Yaya Han has seen cosplay catch on, with more people embracing the idea of dressing up either as characters from their favorite geek properties -- or just their own imagination.

Attending Comic-Con had been Han's Holy Grail, and she finally made it there in 2007, though that first year, there weren't as many cosplayers as she'd expected. Han said the art of cosplay gained traction, with more folks suiting up and more mainstream press showing up to chronicle the capes, wigs and foam weapons until about 2015. That's when she said cosplaying reached a plateau, in part due to the saturation of other conventions.

"San Diego was the place to be seen for a lot of cosplayers," said Han, who has dressed up as everyone from Elektra to Catwoman and Jessica Rabbit.

She chalks up the slowdown to the emergence of numerous culture conventions around the world, as well as the desire of cosplayers to throw on some civilian clothes and take in Comic-Con programming just like everyone else, without having to worry about squeezing their steampunk hoop skirt into an auditorium chair.

Comic-Con has changed in other ways too.

For one, it's gotten harder for convention-goers to get hold of exclusive must-have merchandise you can only get at SDCC, said collector Ken Choy. There's not always enough to go around, but in the world of broader hype, some items are popping up at retailers as what are called exclusives. In one sense, this makes SDCC more accessible to those who can't be there. On the other, those exclusives get a little less, well, exclusive, said Choy, who these days focuses on Harry Potter collectibles and appears on Comic-Con panels about collecting.

"It's like, too much of a good thing is not working out," Choy said of the proliferation of shared exclusives in retail stores.

Comic-Con 2069

So what's ahead for the next 50 years? There's not exactly a clear image of, say, Comic-Con 100, but many agree tech has a larger role to play.

Choy, the collector, lauds SDCC's implementation of a lottery system that decides who will participate in a collecting or signing session. That way, you don't spend your time waiting in line only to walk away without that must-have Funko figure.

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Among those I spoke with, there's a dream floating around that one day, waiting in line at Comic-Con (the queues are notoriously long) will be a thing of the past.

"Every line you want to stand in to get into a panel you want to see -- there's an opportunity cost for the billions of other things that you're not seeing," Salk said.

Queues aside, there doesn't seem to be much debate that SDCC will go strong for a long time. Just how strong depends on whether the current interest in all things nerdy holds out over time.

Steph Forney

"Everything is cyclical," said comic book artist Sean Forney, who's been attending Comic-Con since 2009. "I'm sure at some point it probably won't be as mainstream." However, he thinks there will always be enough to keep the SDCC and geek culture moving forward.

There's certainly potential -- we're about to start a new phase of Marvel movies, there are rumors of a Game of Thrones prequel series and the latest Star Wars trilogy is wrapping up, but clearly it won't be the final stop in the universe. This year's con could be the jumping-off point for a whole other round of reasons to stay invested in Big Geek. Salk sees nerd culture as nearly too big to fail, at this point.

But no matter what happens, longtime attendees hope the event keeps comics at its core, and stays a prime spot to be themselves.

"People come from all around the world to be in a place where they feel like they belong, and they belong to each other," Kim said. "We all need that."

Originally published June 26.