Avengers: Endgame tickets are officially on sale now and that has caused major headaches for quite a few fans and even several major theater chains. In recent years, reserved seating has become the norm for movie theaters in the United States. No longer do we have to line up for hours on end prior to a midnight showing on opening night for a big movie. Instead, modern conveniences allow us to secure tickets well in advance. However, for some of these big movies, that's particularly problematic, as many Marvel die-hards are learning the hard way today.

As expected, presale tickets for Endgame went on sale at all major theater chains today. As was also expected, demand was incredibly high. So much so that theater chains like AMC, Cinemark and the Alamo Drafthouse websites and apps were having trouble handling the load. The Drafthouse site was re-directing traffic to Fandango, while AMC crashed entirely. Other users were experiencing very long wait times to buy tickets. The AMC Theaters Twitter account sent out the following message, doing their best to make light of the situation.

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"We want everyone to be able to grab their Avengers: Endgame tickets, but it looks like we've gotten Thanos' snap. We're working on getting things back up and running, and in the meantime, please keep trying our website and our partner sites!"

Just to give some idea of just how crazy things are, Atom Tickets released some early info. Thus far, Avengers: Endgame has sold three times more tickets on their platform in the first hour of pre-sales than Infinity War did during that same amount of time last year. The first hour of pre-sales for Avengers: Endgame set a new record on Atom, outpacing both Infinity War and Star Wars: The Last Jedi, which now sit at the number two and three spots respectively.

According to an Atom Tickets survey from earlier this year, Avengers: Endgame topped multiple lists by wide margins, including overall most anticipated, most anticipated superhero movie and most excited ensemble cast to see. Many fans took to Twitter to share their experience. Quite a few were frustrated, while others were simply happy that they had managed to secure tickets in seeing that so many were having such a difficult time. Twitter user Daniel Howell put it this way.

"Successfully booking tickets for Endgame was more challenging than the Avengers actually defeating Thanos."

One thing that has made booking tickets so challenging is, not only the demand, but it's confirmed that the movie is 3 hours and 2 minutes in length, meaning that theater chains can only squeeze in so many showings on opening night. So, not only are fans going to have to exercise discipline when it comes to their bladder, but the lengthy runtime has presented other challenges. Marvel is set to release Avengers: Endgame in theaters on April 26.