Outdoor sculptures that require 3D glasses offer a unique fusion of art and optical illusion, transforming public spaces into immersive experiences. Among the most famous is *"Anaglyph Terrain"* by artist Felice Varini, a large-scale installation that uses red-and-blue anaglyph techniques to create depth when viewed through 3D glasses. Another standout is *"Stereoscope"* by Patrick Hughes, a mind-bending piece that plays with perspective and chromatic contrast.

In urban settings, *"The 3D Mural Project"* in Denver features towering anaglyph murals that pop into three dimensions with the right glasses. Meanwhile, *"Lenticular Waves"* by XYZ Collective uses lenticular printing to create shifting 3D effects as viewers move around the sculpture. These works challenge perception, proving that public art can be interactive and technologically innovative.

For travelers, the *"3D Sculpture Park"* in Reykjavik is a must-visit, showcasing multiple anaglyph sculptures set against Iceland’s dramatic landscapes. Whether temporary or permanent, these pieces redefine how we engage with art outdoors—requiring not just sight, but participation.