With fortresses and ski goggles, they defended their territory from enemies wielding snowballs.
About 5,800 people in Seattle, Washington broke the Guinness World Record for the number of people in a snowball fight over the weekend. They brought ice cream scoops to form perfect snowballs and built defences with snow bricks.
There was also a snow slide and some participants even made snow toilets, according to Time.
The camera company Contour filmed the event and edited it together with music.
There was hardly any snow in Seattle on Snow Day, so organizers hauled in more than 30 truckloads, according to the Associated Press. The organizer, Neil Bergquist, told AP the event took more than three months to plan.
Participants bought tickets in advance and received wristbands with bar-codes, which were scanned to monitor the number of people present.
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All that for an official snowball fight that lasted only a minute-and-a-half. However, a Guinness adjudicator was on hand to declare the event a record-breaking success.
A day out of the office on the snowy battlefield seems like a worthy-enough cause, but Snow Day also had a bigger purpose. The snowball fight raised about $50,000 for the Boys and Girls Clubs of King County, according to the Associated Press.
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