The stone arch is one of the simplest and most elegant structures in architecture. But if an arch is built incorrectly, gravity can quickly cause it to crash into a heap. To prevent catastrophic collapses, architects came up with several tricks to keep their arches standing, including buttresses, pointed arches, and pinnacles. In this interactive activity from NOVA, try your hand at constructing a stone arch and learn more about the physics behind it.
Learn more here.