Amid Cairo's brick buildings and heaping piles of trash is a sprawling work of art, which, at first, looks messy and incoherent.

But when you stand on the nearby hillside and read the spray-painted Arabic "calligraffiti," as its creator Tunisian-French artist eL Seed calls it, the message reads loud and clear: "If one wants to see the light of the sun, he must wipe his eyes."

The quote represents the importance of withholding judgment of people just because of their circumstances, says eL Seed, who first visited the community a few years ago. He's called the piece "Perception" for just that reason, hoping to get people to see past the area's physical appearance.

The entire piece took three weeks to complete, and eL Seed says it was done in total secrecy from the Egyptian government due to the country's strict laws forbidding artistic expression.

Here's how his multi-colored vision came to life.