This is a website put together by a Ukrainian woman named Elena who is into urban exploration.
The Serpent's Wall was a ring of WWII forts and bunkers around Kiev built to protect the city from the advancing German Wehrmacht. I thought you guys would like it.
The Serpent's Wall:
http://www.theserpentswall.com/index.html
She also has several websites with many pictures of her various trips to the now abandoned city of Chernobyl. Also very cool. Follow the links and you will find it.
P.S.: Do NOT send her money for one for her photo CD's. You will never get it. That part of the story is a scam to get money from dumb Americans.