From the Pittsburgh Cultural Trust website:
Pyramid XL Sphere by Cyril Lancelin
Cyril Lancelin describes his inflatable sculpture, Pyramid XL Sphere, as a monumental work dedicated to contemplation and exploration. As if emerging from ancient history, the art installation’s stacked, yellow-colored spheres (a nod to the shade of Pittsburgh’s three iconic golden-colored ‘sister’ bridges that span the Allegheny River) create the geometric pyramid shape. Pyramid XL Sphere soars through infinite space. Inside the immersive, geometric sculpture visitors are welcome to experience and discover unknown spaces, being small in the middle of the art, and yet feel totally comfortable in either getting lost or finding their way.