Mackenzie Hall is imploded Feb. 19, 1991.

Photo from the North American Dismantling Corp.

Mackenzie Hall is imploded Feb. 17, 1991.

Photo from the North American Dismantling Corp.

Mackenzie Hall is imploded Feb. 17, 1991.

Photo from the North American Dismantling Corp.

Mackenzie Hall is imploded Feb. 17, 1991.

Photo from the North American Dismantling Corp.

At 10.15 a.m., the implosion of Mackenzie Hall began. Less than a minute later, after the smoke had cleared, all that was left was rubble.

Photo from the Detroit Free Press archives.

Mackenzie Hall is imploded at 10:15 a.m. on Feb. 17, 1991.

Photo from the Detroit Free Press archives.

Smoke appears as the first blasts fire Feb. 17, 1991, as Mackenzie Hall is imploded. The university said it decided to raze the building because it was less expensive than remodeling it.

Photo from the Detroit Free Press archives.