Most of the Um er-Rasas archaeological site has not been excavated. Containing remains from the Roman, Byzantine and Early Moslem periods (end of 3rd to 9th century AD), the site started as a Roman military camp and grew to become a town as of the 5th century. There has been little excavation of the ca 150-m by 150-m fortified military camp. The site also has several churches, some with well preserved mosaic floors. Particularly noteworthy is the mosaic floor of the Church of Saint Stephen with its representation of towns in the region. Two square towers are probably the only remains of the practice, well known in this part of the world, of the stylite monks (i.e. ascetic monks who spent time in isolation atop a column or tower). Um er-Rasas is surrounded by, and dotted with, remains of ancient agricultural cultivation.