Most of us in the Bay Area saw the disaster first from the air and it was an unbelievable sight. A 14-block stretch of Interstate 880, known as the Cypress Freeway, collapsed.
For many of the 42 people killed, it was over in an instant. Some sections of the freeway were crushed so completely, no one could survive. In other areas, there was just enough space between the top and bottom decks to allow some people to get out alive.
"I looked up and the freeway was falling in front of me," said one one witness in 1989. "The car was stopped like a disk brake by being squeezed to a stop by the top and bottom of the freeway."
This man's car was crushed in a space about two feet high.
"I kicked out a passenger window and I climbed out and I climbed down the twisted rebar that supported the beams," he said.
Chaos was everywhere on and around the freeway. People trapped in their cars and volunteers scrambled to find equipment to help.
"Ladders and screwdrivers and whatever they could bring, carjacks, whatever. And they brought them back and we climbed up there with ropes and started rescuing people," said volunteer rescuer William McElroy in 1989.
For hours, volunteers and firefighters crawled between the decks, looking for survivors. One firefighter on the scene was Dave Petersen. He was stunned when he learned his own son might be trapped.
"I knew they were talking about me or my son, and one of them came over and said they did find him and he was alive," said Petersen in 1989.
But just barely. Tim Petersen was trapped in a pick-up truck, crushed to just 20 inches. He was badly injured, but conscious.
"It was loud at first. So as soon as it happened, a lot of horns made contact, so all cars around the horns were blaring. And you could hear people screaming way off in the distance," said Tim Petersen.
It took more than six hours for firefighters to tunnel through the wreckage to Tim's truck. He is still overwhelmed by their bravery.
"You're in a little tiny space like that and there's aftershocks and they know this thing just fell, so they are stuffing themselves down and crawling down in that hole to get this guy who's probably not going to make it anyway," he said.
Firefighters risked their own lives to get Tim out and when he recovered, he joined the Oakland Fire Department, working with the same firefighters who rescued him.
"These guys, they are the true heroes," he said.
Also on the Cypress that night was Mark Hoffman, a new lieutenant.
"I was the first fire officer on the scene and as hard as I tried I couldn't control that incident and it got bigger and bigger and bigger and I'm used to fire - it gets bigger and bigger, then goes out, this thing wasn't going out," said Hoffman.
Twenty years later, Mark says the huge size of the disaster became a catalyst for change. Rescue workers got better equipment and training.
"Quite a few government agencies stepped up their game," said Hoffman.
Mark leads one of 28 urban search and rescue teams around the country, the kind of teams that were called out in Hurricane Katrina. Their high tech gear is packed and ready. A team of 70 can roll out within four hours.
"Search dogs, structural engineers, emergency room physicians, firefighters who are specialized in the use of listening equipment, search equipment," said Hoffman.
That kind of team might have made a difference in the search of the collapsed Cypress, where one victim was not found for four days. But whatever the training, Tim says there's still no substitute for guts and he never forgets the men who rescued him.
"I call them every October 17th, sometime that day and they know it's coming - and they always either hang up on me or say leave me alone, don't bother me with this stuff anymore. But the outcome would have been a lot different and had it not been those guys," he said.
Written and produced by Jennifer Olney.
PROGRAMMING NOTE: Join us for a one-hour retrospective on the devastating Loma Prieta earthquake on Saturday, October 17 at 10 p.m. and Sunday, October 18 at 7 p.m. We'll look back at the damage, how the Bay Area was forever changed, and what still must be done today to prepare for the next "big one."
SPECIAL COVERAGE: Web exclusive content commemorating the 20th anniversary of the 1989 Loma Prieta quake. Includes extended interviews with reporters who covered the quake, as well as city officials and first responders who lived through it all.