The surface of the Géode in Paris. If a polyhedron has triangular faces and has 5 or 6 triangles around each vertex, the vertices with 5 triangles will be exactly 12: this is a consequence of Euler's relation (V-S+F=2).
The image belongs to the sections...:
Polyhedra around the world (3D geometry)
Roofs and domes (Anthology of images)