My landlord had planted it several years ago and it had gone as nuts as the squirrels, smothering the tree next to it then on to conquering the big conifer next door. Not any more!
Grape vines are so vigorous you can cut them back by 70%. I probably cut it back more than that to be fair but I'm sure it'll be fine. I'll be interested to see what it does next...
After (turned out it was holding it's rotten old arbour together too so that half came down with it):