Sorry, don't have a number for Heilongtan and Cloud 9 must have a different contact number now as asiababy has found. Both are easy to find however off County Road 42 in Pinglin. Cloud 9 is first, and well marked, and Heilongtan is another 20 minutes down the road, and also well marked. You'll see signs for it the whole way.
“Everywhere else in the world is also really old” said Prof. Liu, a renowned historian at Beijing University. “We always learn that China has 5000 years of cultural heritage, and that therefore we are very special. It appears that other places also have some of this heritage stuff. And are also old. Like, really old.”http://hikingintaiwan.blogspot.com/