Scientist Pete Kelsey and his team have 3D-mapped the entire island of Alcatraz, discovering Civil War secrets, prisoner escape routes – and looking at ways to preserve the island for the future.

Like many Indian reservations, Alcatraz had no modern facilities or fertile soil. The federal prison had closed six years earlier ... after authorities shut it off, among other hardships, grew ...

The future of Alcatraz lies in one man’s hands ... and other safety concerns including structural damage. Nowhere was off limits. “They gave me the keys to the place,” Kelsey says.