Foursquare Badge – Swarm
To unlock this badge you will need to be part of a check-in swarm to a location that has 50 people checked in. The time frame of the front of the 50 to the back of the 50 is 3 hours.. meaning if you checked in to a location you would need 49 other people to check-in within a 3 hour time period. All 50 members of the swarm must remain checked in. Checking in somewhere else will take you out of the swarm and you will not get credit if the location hits 50.