Clematis virginiana
Clematis virginiana, commonly known as Virgin's Bower, (aka Love Vine, Traveller's Joy, Virginia Virgin's Bower), syn. Clematis virginiana L. var. missouriensis (Rydb.) Palmer & Steyermark ) is a vine of the Ranunculaceae (buttercup) family native to the United States. The name "Love Vine" also is applied to alleged aphrodisiacs, such as Caribbean species of Cassytha, which are unrelated to Clematis, not being in the family Ranunculaceae.
It is a rapidly growing vine which can climb to heights of 10-20ft. It grows on the edges of the woods, moist slopes, fence rows, in thickets and on streambanks, producing white, fragrant flowers about an inch in diameter between July and September.
Pretty, though.