Six children were killed in a school bus crash in Tennessee earlier this month. The investigation is still in its early stages, and there's plenty we don't know. But one thing we do know is that the community of Chattanooga has been changed by the tragedy.

It's something 9Wants To Know investigator Kevin Vaughan found as he chronicled the decades-long aftermath of Colorado's deadliest traffic accident, which Kevin wrote extensively about for the Rocky Mountain News.

It happened nearly 55 years ago, when a high-speed Union Pacific passenger train slashed through a school bus at a rural crossing southeast of Greeley, killing 20 children. The Dec. 14, 1961, crash injured 16 other kids and the driver, Duane Harms.

Vaughan spent months looking into the way the crash rippled through generations. The result was “The Crossing,” a 34-part series based on extensive interviews with survivors, family members and friends of those who died, and hundreds of pages of documents.

After the Rocky went out of business in 2009, the paper’s website ceased to function. Among the casualties was the paper’s presentation of the story, which included videos, original documents, and numerous historic photographs.

In 2015, after obtaining permission to re-publish the series, Vaughan launched a website that hosts the original presentation of the story. It can be found here.