Hi Aemilius, Ihad been there once, year 1998. Wu Tai San is situated in Tai Yuan( from Tai Yuan you need to take a bus to Wu Tai San for about 2 or 3 hours ride.)If you want to go there, the closest airport is Beijing. but plane ticket Beijing- Tai Yuan. The flight from Beijing to Tai Yuan takes about 2 hours. Wu Tai San is famous for it extraordinary power of the Manjusri Bodhisatva. Many people/Buddhists experience the existence of Manjusri Bodhisatva there.
Late Master Hsu Yun( 120 years old famous Zen monk, passed away in 1959) met the real Manjusri Bodhisatva in the disguise as a beggar( later Master Hsu Yun figured it out that this beggar was indeed Manjusri Bodhisava in disguished).
It's called Wu Tai San, because it consists of 5 mountains. You will find the big stupa ( part of Sakyamuni Buddha relics were kept here), and legend said Naga( Dragon spirit) is protecting this place because of the relic. Ok. hope you get the info you want. Omitofo