Neoclassical architecture is a style that emerged in the mid-18th century, inspired by the classical art and architecture of ancient Greece and Rome. It emphasizes symmetry, simplicity, and grandeur, often featuring columns, domes, and elaborate façades. This style sought to convey ideals of beauty and order, reflecting the Enlightenment's focus on reason and rationality. Prominent examples of neoclassical architecture include the Pantheon in Paris and the United States Capitol in Washington, D.C.. Architects like Robert Adam and Thomas Jefferson played significant roles in popularizing this style, which became a symbol of civic virtue and democratic ideals in the 18th and 19th centuries.