Impossible staircase

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The Penrose stairs, famously referred to as the "impossible staircase," showcases a two-dimensional representation of a stairway that accomplishes four 90-degree turns while ascending or descending; nonetheless, this results in an unbroken loop. Despite its logical impossibility, it plays tricks on our perception because it appears as if someone could climb endlessly without gaining altitude. For a clearer understanding of this optical illusion, simply watch the video.