The traditional Vietnamese village, typical of lowland northern and central Vietnam, was a highly nucleated settlement surrounded by a bamboo hedge or sometimes by an earthen wall. Each village had a communal hall ( dinh ) that served as a sanctuary for the cult of the village guardian spirit and as a public meeting hall. Mahayana Buddhist temples were also common. These villages tended to be tightly bounded and relatively closed communities (both physically and socially) with an elaborate community structure, located along roads or waterways or on knolls or hillsides. Houses were built with mud or brick walls, thatched or tile roofs, and earthen or concrete floors. In the more recently settled southern region, especially in the western Mekong Delta, settlements have been more scattered and less tightly bounded, with a less well-defined community structure. Some southern villages had no dinh. Most are strung out along roads or waterways and some households are scattered over the countryside. Houses have walls of woven bamboo, brick, or wood, earthen or concrete floors, and roofs of palm leaves, thatch, or, in recent decades, corrugated iron or metal sheets made from recycled aluminum cans.