DENVER (CBS4)- The old Biomedical Research Building on the old University Hospital campus was imploded Saturday morning with dozens of detonations and a billow of smoke.
Crews shut down several roads surrounding 9th and Colorado during the preparation, implosion and cleanup on Saturday.
A quick series of about 170 small detonations rocked the building over a period of about 30 seconds.
It only took a few seconds for the seven story building to come down. Hundreds watched from the barriers as it disappeared into a plume of smoke that spread out over the Denver metro area and was gone.
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"It was amazing. It was the first time I've ever seen a demolition like that," said observer Jeff Parker.
"I think it was amazing, I think I jumped about a foot," said observer Leana Clark.
Crews decided to implode the building earlier in the year as construction crews determined it was the safest and quickest way to do it.
"We would spend a little over four months taking it down piece by piece," said Saunders Construction spokesman Greg Schmidt.
In the building's place will be a 26-acre development with office space, restaurants, retail, a hotel and housing.
"About 1,100 residential units, 10 percent of which will be affordable housing," said Development Director Frank Cannon.
PHOTO GALLERY: Building Implosion At Old University Hospital
The building and the surrounding buildings on the old University Hospital campus have been vacant for years. The complex was a busy medical campus with thousands of doctors, nurses, patients and medical staff working there. Some are sad to see it go.
"It's a little sentimental watching this go, it's where I met my husband," said Teresa Berryman.
As the walls came down on the building, others were looking ahead to the future.
"This symbolizes a new beginning for this neighborhood and for the City of Denver," said Denver Mayor Michael Hancock.
"Having the opportunity to create a new neighborhood within the City of Denver is exciting," said Cannon.
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