For nearly 44 years, Collin Gau has gone to work at one of Minnesota’s most historic workplaces. His round second-floor office is part of an octagonal granite tower designed nearly a century ago by renowned St. Paul architect Clarence H. Johnston.

The architectural significance is even more noteworthy when you realize that unpaid builders mined the granite from on-site quarries.

“It would have been hard labor,” said Gau, the warden at St. Cloud’s 127-year-old prison. “All the work was done by hand with hammers and chisels. There were no hydraulics yet, so block-and-tackle ropes lifted all those granite blocks.”

Legislators picked St. Cloud’s granite-rich location for Minnesota’s third prison in 1887, figuring the state could make a buck selling inmate-mined stone that came from two quarries inside the prison’s ­original wooden stockade walls.

When other St. Cloud quarry owners complained that the state was undercutting their business with its free prisoner labor, lawmakers halted the commercial operation in 1891.

But inmates were far from off the hook. From 1905 to 1922, they hammered, chiseled and hoisted enough blocks from those prison quarries to build a 22-foot-high stone wall covering a mile and half of the prison’s perimeter. Four-feet-wide at the base and tapering to 3 feet across the top, it’s believed to be the world’s second-longest prisoner-constructed wall. The Great Wall of China used criminals, among thousands of workers, to construct miles of its meandering defenses starting centuries ago.

St. Cloud’s big wall is also a fixture for generations of families driving Up North via Hwy. 10.

“So many people have told me how they would drive by as kids and dad would say: ‘You better be good, or else that’s where you’ll end up,’ ” Gau said.

The prison — technically known as the Minnesota Correctional Facility-St. Cloud — opened in 1889 as the Minnesota State Reformatory for Men. Seventy-seven convicts from the old Territorial Prison in Stillwater were transferred and handed chisels. Among those left behind in Stillwater: Cole and Bob Younger, cohorts of Jesse James’ gang, locked up since the botched Northfield bank raid in 1876.

St. Cloud’s inside-the-wall quarries are now filled in with water. You can glimpse them on Google’s satellite map (

“The history of the place has always fascinated me,” said Gau, who started working at the prison in 1972 as a case manager for 65 offenders.

Nicknamed Gray Stone College, the prison originally included more than 200 acres for farming. Inmates ran a full dairy operation and grew countless potatoes — with proceeds going into state coffers.

Gau said the prison still controls 450 acres of farmland outside the 55 acres surrounded by the stone wall. But the penal farm colony vanished in the late-1960s after four inmates escaped and one was shot to death at the nearby Mississippi River.

The last time prisoners scaled the wall to escape? “Four offenders went over the wall in 1957 by Tower Seven,” Gau said. “They were apprehended but only after hostages were taken.”

Riots have erupted over the years, when prisoners argued for more freedoms such as increased recreational time. Today, St. Cloud’s prison houses 1,100 men and all of the state’s male offenders funnel through the granite walls as part of the corrections department’s intake system. About 400 prisoners are processed there each month.

With all that coming and going, there isn’t much time for inmates to case the joint like the characters in such movies as 1994’s “The Shawshank Redemption.”

If they checked the wall today, they would find plenty of footholds for climbing. The aging stone wall needs massive tuck-pointing with holes in the mortar large enough to fit a hand or a foot.

That’s why state corrections officials are seeking $4 million in bonding money from the Legislature this spring — part of a three-phase, $14 million plan to spruce up the state’s oldest working prison.

Stillwater’s prison, also designed by Johnston, opened in 1914 and replaced the Territorial Prison that had operated along the St. Croix River since 1853.

When the inmates mined the granite to construct most of the buildings inside the St. Cloud prison walls, it became the state’s third lockup. The so-called House of Refuge, a St. Paul jail for young offenders, opened in 1867. Renamed the Minnesota State Reform School, it moved to Red Wing in 1890 and became re-christened again as the Minnesota State ­Training School.

St. Cloud’s prison was originally designed for offenders aged 16 to 30 — a mid-level jail for criminals considered redeemable and fell between the reform school delinquents and the hard-core inmates in Stillwater.

As for Gau, he could have retired by now. He’s 67. “But as long as I still enjoying coming to work,” he said, “in a place with this much history, why quit?”


Curt Brown’s tales about Minnesota’s history appear each Sunday. Readers can send him ideas and suggestions at A collection of his columns is available as the e-book “Frozen in History” at