This looks like some kind of wild hydrangea, but based on the way it has these large flowers opening around the edge, I think it’s Hobblebush. The showy outer flowers are sterile, the tiny inner flowers are fertile. Later will have fruit changing from red to purple. Has low hanging branches that put down roots where they touch the ground, forming webs of roots that hobble walkers—supposedly that’s the origin of the name. Honeysuckle family. Native.

Hobblebush, Witch-hobble, Moosewood (Viburnum alnifolium)