Ancient Roman architecture developed different aspects of Ancient Greek architecture and newer technologies such as the arch and the dome to create a new architectural style. Roman architecture flourished throughout the Empire during the Pax Romana. Its use of new materials, particularly concrete, was an important feature. Roman Architecture covers the period from the establishment of the Roman Republic in 509 BC to about the 4th century AD, after which it becomes reclassified as Late Antique or Byzantine architecture. Most of the many surviving examples are from the later imperial period. Roman architectural style continued to influence building in the former empire for many centuries, and the style used in Western Europe beginning about 1000 is called Romanesque architecture to reflect this dependence on basic Roman forms. The Ancient Romans were responsible for significant developments in housing and public hygiene, for example their public and private baths and latrines, under-floor heating in the form of the hypocaust, mica glazing (examples in Ostia Antica), and piped hot and cold water (examples in Pompeii and Ostia).