The world's leading sci-fi and fantasy event, Worldcon, was forced to restrict ticket sales on Wednesday as the Helsinki Fair Centre saw huge queues. Attendees are no longer able to buy memberships, which include passes for the whole event, with only a limited number of day passes available for purchase.
By noon, all on-the-door day passes for Thursday had been sold out.
Those day passes are limited to two per person. Many of the panel discussion sessions filled very quickly, leaving disappointed sci-fi fans outside.
"There is a limited amount of seats and air," said Worldcon75 press officer Nina Törnudd. "For security reasons we can't admit 200 people to meetings or meet and greet sessions in rooms with a capacity limit of 100."
Worldcon attendees have voiced their displeasure on social media as they've been left out in the cold while just a few fellow enthusiasts make it inside the panel discussion rooms.
Especially popular events on Wednesday included the Always Connected and It's Mandatory workshops, and a panel aimed at Worldcon first-timers.
Törnudd said the congestion was down to increased interest in the run-up to the event, for which organisers were unprepared. They were forced to stop selling full Worldcon memberships to ensure as many fans as possible could see some of the convention.
"We are sorry that this will disappoint potential attendees over the rest of the convention, but believe that our obligation to those who have already paid to attend the convention must come first," organisers said in a statement.
They hope the broader programme on other days will help avoid some of the queues and disappointment seen on Wednesday, with more than twice as many events planned for most days and new areas of the convention centre opened up to sci-fi fans.
The open sales area, or Trade Hall, remains open to the public and free of charge. The event runs through Sunday.