I was at the Lexington Arboretum recently and saw at least fifteen Red Admiral butterflies (Vanessa atalanta) in the same area. I’ve often seen Red Admirals, but usually only one at a time.
After some reading, I’ve discovered these butterflies often migrate south in autumn and north in spring, and I’m guessing that I was seeing part of their northward migration. This one was basking in the sun on a stone column.