That's exactly what Sue Sturdy of Cambridge, Ontario, Canada wants to do. She wants volunteers to knit pieces of yarn until she has enough to blanket a bridge in that city. She already has over one hundred volunteers.
She hopes to have the blanket on the bridge sometime this summer. After the exhibit the blanket will be removed, sections taken apart, washed and then make into scarfs and smaller blankets to be distributed where needed.
I know you think I'm joking, so check the article in my local paper. Sue Sturdy wants to make a cosy for a bridge.
I don't have a contact for Sue at this time, but will check with the newspaper and will post when I have found one.