|Location||810 FM 2821
Huntsville, Texas 77349
|Security class||G1-G4, Administrative Segregation, Outside Trusty|
|Capacity||Unit: 2,300 Trusty Camp: 321|
|Managed by||TDCJ Correctional Institutions Division|
The John M. Wynne Unit (WY) is a men's prison of the Texas Department of Criminal Justice, located in northern Huntsville, Texas, at the intersection of Farm to Market Road 2821 West and Texas State Highway 75 North. The Windham School District has its headquarters in the unit. Wynne, the second oldest prison in Texas, was named after John Magruder Wynne, who served as a prison employee and later as a board member of the prison system from 1878 to 1881. The unit, on a 1,412 acres (571 ha) plot of land, is co-located with the Holliday Unit.
The State of Texas bought Wynne from the last lessees of the facility (Cunningham and Ellis) in 1883. Wynne initially had about 1,970 acres (800 ha) of terrace gardens used to fulfill the gardening needs of the Huntsville Unit. The current unit was dedicated in 1937 and completed in 1939.
In the 1970s, the prison had 17 prison guards in its day shift to oversee 2,600 prisoners. The prison system arranged to have building tenders used to guard the prisoners, making up for the small number of prison guards.
On August 8, 2000 an inmate escaped from the prison by driving a tractor trailer cab through the prison wall while avoiding gunshots fired by correctional officers. The prisoner left the truck on the runway of Huntsville Airport and fled into a vehicle; state officials believed that the man's wife drove the vehicle. Police officers with tracking dogs found the man and his wife under a tree less than 7 miles (11 km) from the Wynne Unit. The state said that the offender "reportedly" was taken with force, while the wife surrendered peacefully.
In 2007 two inmates from Wynne escaped. During the incident the escape vehicle hit 59-year old correctional officer Susan Canfield, killing her. Both inmates have been found and rearrested. The driver was executed on December 3, 2013. 
In 2008 an Offender escaped the Wynne Unit using a child's bicycle. He was taken back into custody less than 24 hours later.
Wynne has a box factory, a computer recovery factory, has the only license place factory for the state and works with the 3M company. A mattress factory, which provides all of the beds for the state colleges, is at the Wynne Unit, as well as a mechanic shop with diesel repair, a signs and plastics plant, and a sticker plant. All of the state issued car registration stickers are also made at the Wynne Unit. It has been shown that the Wynne Unit generates around $1 Million a week for the State of Texas  The Windham School District has its headquarters in Building B in the Wynne Unit.
- David Ruíz (plaintiff of Ruiz v. Estelle)
- David Crosby (member of Crosby, Stills, and Nash) was held for 5 months in the Wynne State Farm. "http://www.rockandrollroadmap.com/other-u.s.-area-misc/wynne-unit-david-crosby-imprisoned-here/view-details.html"
- "Wynne Unit." Texas Department of Criminal Justice. Retrieved on September 29, 2011.
- Texas Department of Criminal Justice. Turner Publishing Company, 2004. 119. ISBN 1-56311-964-1, ISBN 978-1-56311-964-4.
- Walt, Kathy. "TEXAS PRISONS AFTER THE REFORM/ WHAT RUIZ WROUGHT/ New challenges confront a prison system that has undergone a profound transformation." Houston Chronicle. Sunday March 28, 1999. A1. Retrieved on December 31, 2011.
- Glenn, Mike and Terri Langford. "Second escapee caught after prison guard's death." Houston Chronicle. September 25, 2007. Retrieved on June 3, 2010.
- "Contact Information." Windham School District. Retrieved on January 1, 2010.
- "Travel Regulations for Employees" 7.28-4. Windham School District. September 1, 2005. Page 5 of 15. Retrieved on January 1, 2010.
- Perkinson, Robert. Texas Tough: The Rise of America's Prison Empire. First Edition. Metropolitan Books, 2010. p. 260. ISBN 978-0-8050-8069-8.
- Wynne Unit - Texas Department of Criminal Justice
- List of prisoners in the Wynne Unit - The Texas Tribune