physical training for youth. The Altar of Augustan Peace (Ara Pacis Augustae) was located there, as was an obelisk imported from Egypt that formed the pointer (gnomon) of a horologium. With its public gardens, the Campus became one of the most attractive places in the city to visit. City planning and urban lifestyles had been influenced by the Greeks from an early period, and in the Eastern Empire, Roman rule accelerated and shaped the local development of cities that already had a strong Hellenistic character. Cities such as Athens, Aphrodisias, Ephesus and Gerasa altered some aspects of city planning and architecture to conform to imperial ideals, while also expressing their individual identity and regional preeminence. In the areas of the Western Empire inhabited by Celtic-speaking peoples, Rome encouraged the development of urban centres with stone temples, forums, monumental fountains, and amphitheatres, often on or near the sites of the preexisting walled settlements known as oppida. Urbanization in Roman Africa expanded on Greek and Punic cities along the coast. The network of cities throughout the Empire (coloniae, municipia, civitates or in Greek terms poleis) was a primary cohesive force during the Pax Romana. Romans of the 1st and 2nd centuries AD were encouraged by imperial propaganda to "inculcate the habits of peacetime". As the classicist Clifford Ando has noted: Even the Christian polemicist Tertullian declared that the world of the late 2nd century was more orderly and well-cultivated than in earlier times: "Everywhere there are houses, everywhere people, everywhere the res publica, the commonwealth, everywhere life." The decline of cities and civic life in the 4th century, when the wealthy classes were unable or disinclined to support public works, was one sign of the Empire's imminent dissolution. In the city of Rome, most people lived in multistory apartment buildings (insulae) that were often squalid firetraps. Public facilities—such as baths (thermae), toilets that were flushed with running water (latrinae), conveniently located basins or elaborate fountains (nymphea) delivering fresh water, and large-scale entertainments such as chariot races and gladiator combat—were aimed primarily at the common people who lived in the insulae. Similar facilities were constructed in cities throughout the Empire, and some of the best-preserved Roman structures are in Spain, southern France, and northern Africa. The public baths served hygienic, social and cultural functions. Bathing was the focus of daily socializing in the late afternoon before dinner. Roman baths were distinguished by a