Is that a bittersweet? Sarah

Sarah, I have no idea what it is. I don't think it is bittersweet because it has thorns all along the stem. The berries will turn black as there is another cluster back further on the vine that have turned black. I have searched and searched and I can't find anything like it. Like I said it looks just like a raspberry bush except the berries are really different. I hope someone knows what it is. If the birds like it, I will move it from behind my other bushes. It is a very pretty vine.

I have seen Rubus allegheniensis (common black raspberry) canes that were 15' long. I think that's what you have.

I think so too.
I have seen it in the wild pretty often around Montreal, in abandoned farmlands, etc.
And some blackberries species or varieties can be trained to grow more or less like a vine.