Ancient Roman architecture of being in their houses, as they instead would go to public baths, and engage in other communal activities. Many lighthouses were built around the Mediterranean and the coasts of the empire, including the Tower of Hercules at A Coruña in northern Spain, a structure which survives to this day. A smaller lighthouse at Dover, England also exists as a ruin about half the height of the original. The light would have been provided by a fire at the top of the structure. All Roman cities had at least one thermae, a popular facility for public bathing, exercising and socializing.
Ancient Roman architecture of these developments are described by Vitruvius, writing in the first century AD in his work De Architectura. Although concrete had been used on a minor scale in Mesopotamia, Roman architects perfected Roman concrete and used it in buildings where it could stand on its own and support a great deal of weight. The first use of concrete by the Romans was in the town of Cosa sometime after 273 BC. Ancient Roman concrete was a mixture of lime mortar, aggregate, pozzolana, water, and stones, and was stronger than previously-used concretes. The ancient builders placed these ingredients in wooden frames