Secret Underground
- Episode aired Dec 10, 2010
- TV-PG
A look at underground real estate including illegal drug smuggling tunnels, Las Vegas flood controls, and a salt mine that doubles as a vault for classic films and government documents. Also... Read allA look at underground real estate including illegal drug smuggling tunnels, Las Vegas flood controls, and a salt mine that doubles as a vault for classic films and government documents. Also featured is the National Research Lab in Oak Ridge.A look at underground real estate including illegal drug smuggling tunnels, Las Vegas flood controls, and a salt mine that doubles as a vault for classic films and government documents. Also featured is the National Research Lab in Oak Ridge.