The Great Pyramids of Giza and The Great Sphinx in Cairo, Egypt were lit blue for the Light It Up Blue campaign on World Autism Awareness Day Thursday, April 2.

Pyramids & Sphinx Lit Blue

The Egyptian Autism Society organized the lighting of the pyramids and sphinx, which was coordinated with Egypt’s antiquities ministry. The iconic structures joined thousands of other national monuments and landmarks in marking World Autism Awareness Day with the blue lighting.

“The move is a part of an initiative that aims to increase social awareness on the importance of supporting children who live with autism,” Antiquities Minister Mamdouh el-Damaty told the Cairo Post.

The pyramids, built circa 2560 BC, are the oldest of the Seven Wonders of the Ancient World.

In addition to the pyramids and the sphinx, New York’s Empire State Building and One World Trade Center, La Basilica de la Sagrada Familia, China Millennium Monument, Taipei 101 Tower and the Helmsley Building also lit up blue.

“Light it Up Blue is actually a world wide event, because April 2 is Autism Awareness Day,” Michael Bell, who works for an Autism organization in Ohio, explained. “It is a day that you really want to spread the word about autism awareness. Us parents, we do it everyday, but this is for the community to spread autism awareness.”

Autism is the third most common developmental disability.