light blue in model B); and one with a diamond-shaped keystone (the Gothic arch, model C). Flying buttresses act the same way ancient Roman columns did, countering the horizontal force of the arch.

Finished in 315 C.E., the Arch of Constantine is one of Rome’s three surviving ancient triumphal arches, each erected to honor a person or event. This arch commemorates Constantine I’s 312 ...

Rome's ancient Arch of Constantine was hit by lightning during a heavy storm, causing some fragments to fall off, an official said Wednesday. "All the fragments were recovered and made safe ...