Bridges are means of passage across places that are difficult to cross. Rivers, canyons and other obstacles become easier to cross because of them.

That also makes bridges some of the best places to block passage. The history of war is full of battles for control of bridges, and defenders often destroy them to obstruct advancing armies.

That makes a bridge useful as a metaphor too. Here, the superstructure of an old railway bridge contains a passage running parallel to the deck above. You can see that passage is there, but you can’t quite get a clear view through it. It is repeatedly obstructed.

Hence the title, Obstruction.

If you’ve ever had a moment when the way forward seemed clear but progress was blocked, this image is for that moment. The obstacles we so often have to pass through are all here.