Niantic is issuing refunds to players who attended the "Pokemon Go Fest," after the gathering was plagued by connectivity and server problems as well as mile-long lines that prevented attendees from participating in the event.

The game announced that participants will be given a full refund for the cost of their tickets. They will also be receiving $100 in Pokecoins, as well as the game's first legendary Pokemon, Lugia.

"We appreciate the patience of all the Trainers who joined us in Chicago this weekend," said the "Pokemon Go" team on their website, adding, "We will strive to make sure our experiences are of the highest quality going forward."

The problems began even before players could enter Chicago's Grant Park, the venue for the festival. Participants, including those with early-access wristbands, waited in long lines around the venue, leading to more than two hours of waiting in the sun.

Inside the park, a host of connectivity issues and server malfunctions rendered the game unplayable for most of the day. So many gamers trying to play the game at once flooded the servers and overloaded cellular networks in the area. Niantic Chief Executive Officer John Hanke took to the stage to address the ongoing connectivity problems and was met with resounding boos and chants of "We can't play."

Around 20,000 Pokemon fans gathered for the "Pokemon Go Fest" as part of the game's first year anniversary celebration. The event promised players the chance to catch a variety of Pokemon, as well as the opportunity to participate in team events throughout the day in order to unlock the recently announced legendary Pokemon. It was supposed to culminate in a grand raid, battling a legendary Pokemon as it appeared for the first time.

Despite the difficulties faced during the festival, legendary raids have been unlocked in the game. Players will be able fight and catch the game's first two legendary Pokemon, Lugia and Articuno.