They were everywhere!
While driving on North Carolina's Blue Ridge Parkway, Rachel and her 11 year-old daughter came upon a river of butterflies flowing at 400 monarchs per minute:

"At the Haywood Gap section — the land flattens out a bit, and the road skirts the edge — the butterflies were concentrated, streaming in overhead, touching down on the purple and yellow wildflowers at the overlook and continuing on in a southwesterly direction. They were everywhere!" 10/3/12 Waynesville, NC

Image: Rachel T.