Two days before our package arrived, a swarm moved into the hive! Bees had been checking out the hive for weeks, but it looked like they were just robbing the remaining honey. I stopped thinking it was scouts looking to relocate their hive. But then – Lo did the sky darken and fill with the buzzing of thousands of honeybees! We followed them to the front yard where they filled the sky, and then the yard, and then settled on the hive itself. They bearded on the outside, they covered the top bars under the lid, and they rolled out from the door. It was awesome.
Source: Swarm! | Sustainable Scientist