How do you move a technology conference with 30,000 attendees online?

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Each June since 2017, CognitionX, a London-based market research and conference business, has hosted one of the world’s largest annual gatherings devoted to the impact of artificial intelligence and other new technologies on society and business.

Last year, more than 20,000 people attended the three-day CogX “festival of A.I. and emerging technology” in London’s King Cross district, where they listened to 687 speakers participating in talks and panel discussions held on 12 different stages.

But how do you hold such a massive gathering in the midst of a pandemic? “We looked into it,” Charlie Muirhead, the serial technology entrepreneur who is CognitionX’s founder and chief executive officer, says. “We prepared a full health and safety plan of what would have been required to hold it this year as a physical event, with social distancing. But the conclusion was: We couldn’t do it.”

This became especially apparent, Muirhead says, after the U.K. government announced that while it was beginning to ease the country’s lockdown, non-essential businesses would not be allowed to resume operation until mid-June, while hospitality businesses—such as bars and restaurants—would not be allowed to reopen until July at the earliest.

Muirhead and his CogX team debated whether to postpone the event until later in the year. But they worried about scheduling clashes with other local tech-related events, such as London Tech Week, that have also been shifted from the summer to the autumn.

In the end, CogX decided to move online as a virtual event. Plenty of other companies with events businesses, including Fortune, have tried to hold virtual events. But CogX’s ambitions, in terms of the number of participants and how closely it wanted the digital experience to mimic its past live events, were unique.

In fact, CogX planned to expand both the number of attendees—catering to an online audience of up to 50,000 people—and the amount of content in the festival. This year’s CogX, which kicks off in London on Monday morning, will feature 18 different virtual “stages” and 324 hours of simultaneous programming on topics ranging from the future of work to technology and ethics to cybersecurity.

“If we were going to do it, we wanted to do it big,” Muirhead says, noting that CogX has already livestreamed the festival for the past few years, enabling it to build a global audience.

Fulfilling this ambition has required CogX to create a bespoke virtual summit platform by integrating six different pre-existing livestreaming and digital conference software programs into a single front-end user interface. “Suffice it to say, there was no off-the-shelf solution that could do all of this,” Muirhead says.

The end result is, he says, is an attempt to recreate—as much as possible—the kinds of networking opportunities and interactions that physical, live events offer.

This year’s CogX includes a virtual expo where participants meet with representatives from technology companies, along with virtual one-on-one meetings that participants will be able to schedule through the conference platform. There will also be about 100 different side events, hosted by CogX’s sponsors and partners, that will take place on the CogX software platform over the course of the three days.

CogX has developed an A.I.-powered matchmaking system that recommends to attendees others whom they might benefit from connecting with during the festival. The conference is also offering a concierge service that will help book meetings for attendees, for an additional fee.

CogX created a tiered pricing scheme, ranging from some free tickets that people can apply for online, to a premium Global Leadership Summit pass, which attendees have to apply for and which provides access to a separate “festival within the festival.” This Summit is aimed at C-suite executives, startup entrepreneurs, government officials, non-profit leaders, and prominent academics, Muirhead says. The talks and discussions for these 4,500 passholders will be held according to the Chatham House Rule, meaning no one can be quoted by name, in order to facilitate as candid and open a dialogue as possible, he says.

CogX chose “How do we get the next 10 years right?” as the theme of this year’s festival. That theme was broad enough to encompass a range of global challenges, from the coronavirus pandemic to climate change, Muirhead explains. And while CogX began focused largely on artificial intelligence, the conference has been broadening its agenda to take in the impact of technology on society overall.

Former U.S. Secretary of State John Kerry will be headlining the festival with a keynote address on Monday. Other speakers are set to include former U.K. Prime Minister Tony Blair and former U.S. Ambassador to the UN Samantha Power. There will also be prominent venture capitalists, such as Skype co-founder Niklas Zennstrom, and Nicola Mendelsohn, who is Facebook’s vice president for Europe, the Middle East and Africa.