The Yingzao Fashi is the oldest complete technical manual on Chinese architecture. The Chinese followed the state rules for thousands of years so many of the ancient, surviving buildings were built with the methods and materials still used in the 11th century. Chinese temples are typically wooden timber frames on an earth and stone base. The oldest wooden building is the Nanchan Temple (Wutai) dating from 782 AD. However, Chinese temple builders regularly rebuild the wooden temples so some parts of these ancient buildings are of different ages. Traditional Chinese timber frames do not use trusses but rely only on post and lintel construction. An important architectural element are the dougong bracket sets. The Songyue Pagoda is the oldest brick pagoda dating to 523 AD. It was built with yellow fired bricks laid in clay mortar, with twelve sides and fifteen levels of roofs. The Anji Bridge is the world's oldest "open-spandrel stone segmental arch bridge" built in 595-605 AD. The bridge is built with sandstone joined with dovetail, iron joints.