Ancient architecture refers to the building styles and structures created by early civilizations, such as the Egyptians, Greeks, and Romans. These designs often included monumental buildings like temples, pyramids, and amphitheaters, showcasing advanced engineering techniques and artistic expression. Key features of ancient architecture include the use of durable materials like stone and brick, as well as distinctive elements such as columns, arches, and domes. Structures like the Parthenon in Greece and the Colosseum in Rome exemplify the grandeur and functionality of these early architectural achievements.