It was an unconventional rescue mission: A young assistant geography teacher and a grad student were dispatched to save a set of fire insurance atlases from the trash. Getting to them would involve borrowing the university truck, driving 13 hours in a day -from Los Angeles to San Francisco and back again. Memories of exactly when it happened (aside from a spring sometime in the early 1970s) and how many maps they saved are fuzzy, the atlases are anything but.

Each of the rescued maps document the minute details that made up individual buildings and cities across the United States, particularly the Western US, from the 1880s to the 1960s, down to the thickness of the walls and the number of sprinkler heads in each building.

That amount of detail on a map is rare today, but at the Sanborn Map Company, which made and updated hard cover atlases from the 1860s all the way to 2008, those details were the norm. They leased their maps out to fire insurance companies who needed precise details about buildings to assess fire risks and decide rates without having to send out an insurance agent to every location.

But by the 1970s those atlases became less popular as insurance companies changed the way they assessed risks. So when the Sanborn Company, which still makes maps today – though with fewer minuscule details – was moving out of their San Francisco office, they decided to get rid of the historic atlases in that office. And that’s when young Professor Elliot McIntire, now 76, picked them up and brought them back to the Geography Department at California State University, Northridge, just outside Los Angeles.

The Geography Department head, Robert Lamb, had sent McIntire to ‘do a service to the department’, McIntire remembered, laughing.

‘He got a hold of me and said, “Can you go up and pick these up and we need to do it right now because they’re going to dump them”. So we got a university truck, drove up to San Francisco and loaded it up,’ McIntire told DailyMail.com.

‘I remember it was kind of a hectic day… I think we may have been worried about rain. So we were kind of in a hurry to get them under cover.’

McIntire doesn’t remember how many atlases they rescued, but he does remember they were heavy. At about 24 inches by 26 inches, an atlas could weigh up to 40 lbs.

‘If those atlases had been trashed, then all of that information would have just been lost,' he said. 'So, from that standpoint, it was a good thing. I’m glad I did it. And I’m glad the department has that collection.’