This only requires having the right perspective.

It's on the ground.

You may have walked over it many times.

The shape is stretched toward a particular direction.

Stand at the top of the tower in town and look towards the bridge. The dirt path across the wooden bridge will form the shape.

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It involves the wooden bridge to town.

It requires a certain perspective.

You must be at a high vantage point to view the shape.

The shape is formed from the dirt path going across the bridge to town.