When shooting B/W film while we are hiking I find my self often taking pitcures with fenches (and also benches, see the Lonely benches thread )
A few examples all are as mentioned film images (scanned negatives)
A lonely fence by Photobygms, on Flickr
Sturdy wooden gate by Photobygms, on Flickr
Fence with cattle grid or cattle gaurd by Photobygms, on Flickr
A wooden Fence by Photobygms, on Flickr