What kind of vine is this? I've seen it growing in the wild before.
Where is this plant growing?
That looks like a member of the cucurbit family, Cucumber, melon, squash.
Yep, if toward the GreatPlains or SouthWest, I'd say buffalo gourd.
Coyote Gourd ... if you like it, it's not a weed. It makes a nice easy-care ground cover. Comes back from a tuber every year, very drought tolerant.
Thank you for identifying this vine. It's growing in an empty low in southern California.