Although the Romans adopted aspects of ancient Greek architecture, Rome, Italy, still made our list of top architecture cities. The city has awesome architecture witnessed by the beauty of the Colosseum (pictured). It was built in 72 AD and is considered one of the greatest works of Roman architecture and engineering. Tourists can also see other ancient Roman architecture in Aqueducts, the Pantheon, Temple of Vesta, the Vatican and Baths of Caracalla.