This document discusses different types of long span structures with spans larger than 20m. It describes various beam types used in long span structures like castellated beams, tapered beams, stub girders, and lattice beams. It also discusses other structural elements like trusses, arches, and cables that can be used to create long spans. Specific types of trusses and arches are defined along with examples of famous long span structures from around the world that use these elements.