CU-Boulder has been around longer than Colorado's been a state.

Walter Blankenship, or Uncle Walt as he’s known around campus, graduated from the university in 1989. He is the historian for the CU marching band, but he also leads an annual tour of the school’s haunted buildings.

“The famous one is of course the murder in Mackey that happened in July of ’66," he says.

Some of the students that took Uncle Walt’s tour have heard some creepy things in the old concert hall.

“They would go up there between 1 and 3 a.m. and they’d sit there,” Walt says, “and they said, 'Oh yeah, you can hear the scream and you can hear the organ play.’” But there is no longer an organ in that room.

Uncle Walt offers his ghost tour to students every year typically around Halloween.

Watch photojournalist Mike Grady's story above.