Nearby to the cache site is an old bridge, alongside the newer road bridge. We don't know anything about the bridge, but maybe you do. Why don't you tell us, and everyone else, about it.
The cache is a small black cylinder containing log book and pencil. It's not on the road or on the side of the road so don't look there. The road can be busy so watch the young ones.
sp8sm8 & ags