Get rare access to this sculpture, part of Ai Wei Wei’s @Large exhibit, in the lower gun gallery of the New Industries Building on Alcatraz. The giant metal wing is composed of reflective panels from solar cookers in Tibet, contrasting imagery of flight with the piece’s own captivity and bulk (it weighed more than five tons). Visitors could only peer at Refraction through cracked and rusted windows, but you can walk up and around the large wing. Continue through the building to find the secret tunnel access to the outside. Ai Wei Wei is a Chinese contemporary activist who works in sculpture, installation, photography, film, architecture, curation, and social criticism. The @Largeexhibit was open to the public from September 2014 through April 2015. Alcatraz Federal Penitentiary was in operation from 1934 until 1963, during which time it was famous for being virtually impossible to escape from. Today, Alcatraz is a public museum and part of Golden Gate National Recreation Area.