70 years ago Sunday, an explosion was heard around the world.
And the East Texas town of New London was changed forever.
On Sunday, dozens of people gathered at the site of the blast.
Survivors were among those who gathered to remember the 300 students and faculty members who were killed that day.
The explosion was caused by a natural gas leak. A leak was ingnited in the school's basement; the blast destroyed the brick building.
"It took fourty years for the healing to begin and they had their first reunion in 1977, people started coming back talking about those
experiences and they started to heal," said museum tour guide John Davidson.
Because of the New London explosion, methyl mercaptan was added to natural gas.
The additive is what gives the gas an odor to detect leaks.
Walter Cronkite covered the tragedy back then, when he was a reporter.
He called the disaster "a day a generation died."
This memorial standing tall right here in the middle of town is a constant reminder of the lives that were lost that day.
And many of the survivors, now in their eighties, say it's a day they will never forget.
"Only five minutes remained before dismissal time when the explosion came which brough such havoc as to to shock the entire nation."
Old new reports bring back March 18th, 1937 back to life.
Some 300 students and faculty members died after a natural gas leak caused the New London School to explode.
70 years later, survivors still come back to remember the tragedy.
"Just like it happened yesterday, it's something that stays with you... you never, never forget it," said survivor Lucille Dalmuth.
Lucille Dalmuth was one of the few people who made it out alive.
When the explosion happened, she ran outside to the football field.
Minutes later, her parents drove up.
Dalmuth's younger sister died that day.
"My mom and dad said it was hard losing one, and there were some people who lost more than one child here that day."
John Davidson also lost a loved one in the blast.
He was born three years after the tragedy and has learned about his sister through talking with her friends.
"Really, I didn't know a whole lot about here because like everybody else in this community, mother and daddy would not talk about it," said Davidson.
Charles Dial ran home to get his band uniform that fateful day.
By the time he got back, the school was gone.
"There were dead bodies all around, people were hurt, laying around, but at that time people had started to accumulate and
taking their kids to different places," said Dial.
The writings on the New London Museum walls tell the story of March 18th, 1937.
It's a day these survivors say they will never forget.
This is the building where the kids go to school today; it actually overlaps the old school by about 10 feet.