Bees Swarm Like Angels

I had the craziest experience once.  A swarm of migrating honey bees decided to use my tree as a pit stop.  I later looked it up, and there must have a been a queen in there somewhere. That's what all these bees were doing: protecting their queen! I've never seen this happen before and I've never seen it since.  

This brood was heavy!

Ew ew ew ew ew ew.

I wish I had recorded the sound. They were so loud!!

And then as suddenly as they appeared - they dispersed!

They only left this wax to mark their passing.

Have any of you seen this in your yard?  Post in the comments!