DENVER — Two-and-a-half pounds of dynamite will get your attention. That's enough explosive to turn an SUV in to a convertible.

On a November morning in 1919, four similarly-sized explosions put a charge into Homecoming week at the University of Denver.

According to the Denver Post, the shock waves blew out windows on campus and startled students. Some of the damage is still visible today.

Today, that would be considered an act of terrorism. Back then, it was a prank -- allegedly pulled off by the Colorado School of Mines.

Denver Post DU Mines rivalry cartoon
Denver Public Library

"Back then, it was considered clean fun," Mines Athletic Director David Hansburg said. "But I do think 20 sticks of dynamite could be construed as excessive force."

Excessive force sums up what happened later that day. A group of DU students traveled to Golden to "get even" -- at least to add decoration to the giant 'M' on the side of the hill.

Big mistake.

The Rocky Mountain News reported the group was captured. Their heads were shaved and branded with scarlet letters in silver nitrate -- meaning those 'M's didn't come off for months.

Like prisoners or war, they were paraded through town along with a Denver Post reporter who had been kidnapped for what Mines students considered "slanderous" coverage.

Denver Post DU Mines football rivalry
Denver Public Library

If this sounds like the Wild West, keep in mind that 100 years ago Denver was still considered to be just that.

So how do you explain this level of madness and mayhem? Chalk it up to school spirit.

The Denver Post reported that the two student bodies agreed to ceasefire, allowing for football. But the score wasn't settled on the field. The game was a dud as they played to a scoreless tie.

Denver Post DU-Mines football rivalry
Denver Public Library

'Tis the season for college football rivalry games, like the Border War or Iron Bowl featuring schools with a history hatred.

But they don't hold a candle to what went down in Denver a century ago. It's a story that will blow your mind.