Well ... this one is!
This sculpture of Carrara marble by Enrico Cerrachio in the Fort Lincoln Cemetery is a "Living Sculpture" as the historical marker indicates:
This unusual feature was created by the famous sculptor, Enrico Cerrachio. Should you walk across the arm of the cross, formed by the walkway, you will observe the that the eyes and entire head appear to turn and look directly at the beholder at all times. This illusion is created by an ingenious method of sculpturing, which fulfills the Biblical quotation, "The eyes of the Lord are in every place keeping watch, upon the evil and the good." (Proverbs 15:3)The uncanny effect of this sculpture is that the eyes and whole face of Jesus follow you as you move right and left in front of the sculpture. From the left side, Jesus looks leftward toward you:
From the right side, he looks rightward towards you:
He even looks down.
Illustrating the proverb, "The eyes of the Lord are in every place keeping watch, upon the evil and the good."
This is an instance of the pretty well known "Hollow Face Illusion." The eye is fooled into interpreting the concave face as a convex face. But even more strangely, the perspective is such that the face follows you. The diagram below shows how this works:
With perspective reversed, the concave face appears to turn toward you as you move, rather than away from you. Jesus seems to look toward you because he's really looking away.
This particular instance of the illusion provides pathways in the shape of a cross to encourage viewers to see the illusion.
Sit on the left-hand bench and Jesus looks at you; sit on the right-hand bench, ditto.
From the right-hand bench, the sculpture looks like this:
and from the left-hand bench ... well, you know:
To dispel the idea that this illusion depends in any way on its religious content, watch this Dragon video:
or you can do-it-yourself by downloading this PDF and building your own dragon.