Rare tour of the only federal weed farm in America

Dr. Sanjay Gupta puts medical marijuana under the microscope again with "Weed 3: The Marijuana Revolution" at 9 p.m. ET Monday on CNN, followed by "High Profits" at 10 p.m., a CNN Original Series exploring the business of legal, recreational cannabis in Breckenridge, Colorado.

(CNN)Since the 1970s, the Marijuana Project at the University of Mississippi, known as Ole Miss, has been the sole provider of marijuana for federally approved research in the United States. The farm is strictly controlled by the Drug Enforcement Agency (DEA) and the National Institute on Drug Abuse (NIDA).

Between its inception and 2007, the farm supported only a small amount of research because there was little to no demand by scientists. In Spring 2013, when Dr. Sanjay Gupta first visited the Marijuana Project, there was nothing growing in the fields because of this lack of demand. But when he returned a year and a half later, it was a much different story. Acres of the farm were teeming with research-grade medical cannabis in anticipation of a renewed interest in government-approved research.
Photography by Rich Brooks, CNN