6 × 3 = 18. A hexagonal prism has 18 edges. Image caption, The vertices of a prism are at each end of the 3D shape. The number of vertices is twice the number of vertices of an end face.

For example, in the prism below, the cross section is a hexagon. This is called a hexagonal prism. Some 3D shapes, like cubes and pyramids, can be opened or unfolded along their edges to create a ...