Cultural help!

This is driving me crazy. I was trying to remember the specifics of a tradition that I want to say was Tibetan or maybe even Scottish. The idea is to hang ribbons or strips of cloth from wires or trees to commemorate people that have died. I want to say that I've seen pictures of a square where the entire skyview is covered with these ribbons.

Could anyone point me to a reference to this? Or did I dream up the whole thing?

Many thanks!