The rune stone has been smashed to pieces, but most of it was re-discovered and it was mended again. It says that it once stood next to a bridge, and my guess is that when the bridge needed to be replaced by a bigger one, they took whatever building material there was nearby = this rune stone, split it into smaller parts and used in the bridge. There are many, many examples of that. Sometimes the rune stones were found and "saved", while other times they are still there in these bridges. Here's one of them : U 1119.