This temple's main hall dates to 857 and contains a statue of Sakyamuni surrounded by other colourful statues with 296 arhat (罗汉, luóhàn) in the flanks. The hall is the third-earliest preserved timber structure in China, so is exceedingly rare. The icons are said to date from the Tang and Ming dynasties, but look much newer. The Manjusri Hall (on your left as you walk up) has extraordinary 15th-century frescoes (of arhat) that actually look their age.
Behind the main hall is a sexagonal ancestral pagoda built with white bricks in the 5th century.
Foguang Temple is set among farmland 5km outside the small town of Doucunzhen (豆村镇). From Wutai Shan, hop on a bus to Doucun (¥17, one hour), then taxi the remaining distance (under ¥40 return). There is also a local bus (¥1) from Doucunzhen that runs part of the way. You will need to walk the remaining 2km, but it's a pleasant journey on foot.