Once again – lines.
Why have a boring grate when you can have a geometric one?

The original wasn’t much different. I made it black and white and increased the clarity. I decreased the contrast to be able to see some of the metal of the grate underneath. I increased the highlights and whites and made the shadows just a tad darker. I sharpened the whole image and decreased the noise. I also straightened the image as much as I could.
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