stairwell, Forney said the evacuation reminded him of something familiar back home.

 It was like Houston traffic at 5 p.m.,  he said.  It was stop and go the rest of the way. 

There was no running and, according to Forney, little chaos. People moved slowly and orderly down the tower, one step at a time.

The descent took roughly 68 minutes.

At one point, Forney and a colleague encountered a woman named Juliette standing in the stairwell around the 19th floor.

 She said,  I can't go anymore,'  Forney recalled.

The two men helped carry her belongings and continued down with her. Years later, Forney said Juliette's husband, a Holocaust survivor, told the two men he believed she would not have survived without their help.

 I don't consider myself a hero,  Forney said.  This was a lady who was not moving and maybe it was the Texan in me that wanted to help her.

 It was like a war zone'

Reaching the bottom of the North Tower did not immediately bring Forney to safety.

First responders directed evacuees underground in an effort to protect them from falling debris. While Forney was making his way through the underground complex, the South Tower collapsed.

It was the second time that morning he believed he was going to die.

Forney said he was pelted by pieces of glass and thought the ceiling above him was going to collapse.

When he eventually emerged onto the streets of Lower Manhattan, he barely recognized the city.

 It was like a war zone,  he said.  Everything turned to one color, gray. 

Dust and debris covered the ground and continued falling through the air.

Forney said he was still operating almost entirely on instinct, focused on getting away.

Later, while walking with his colleagues, he heard a collective gasp. He turned around and watched the North Tower, the building where he had started his workday hours earlier, collapse.

Only then did the enormity of what had happened begin to register.

He said one of his colleagues told him,  We're under attack. 

 That's when it dawned on me,  Forney said.  Oh my gosh, you're right. 

One phone call home

Forney's next priority was letting his family know he was alive.

With cellphone service disrupted, he found a payphone and called his father's office in Houston. He knew one call there could quickly spread the word to his parents, his wife and other relatives.

Friends later told him they could hear the shock in his voice.

From Lower Manhattan, Forney walked roughly 12 or 13 miles back to his apartment on the Upper West Side. He estimates he finally made it home around 3 p.m.

Shortly afterward, he went to a hospital because of what he had inhaled while trapped underground. Forney said he received a clean bill of health, but concerns about the long-term effects have stayed with him.

 I can't live in that fear,  he said.  I just choose to refocus my attention on life, on living, right? Because I did survive and I am alive. 

 My therapy has been telling my story'

Twenty-five years later, Forney says the memories have not faded.

 It feels like it was yesterday,  he said.

Forney said he has never gone to therapy specifically for what he experienced on 9/11. Instead, he found another way to process it.

 My therapy has been telling my story,  he said.

Days after the attacks, a colleague encouraged him to write down everything he could remember. Forney initially emailed his account to only a handful of friends and relatives.

The story spread.

Before long, messages were coming back from people he had never met, including people across the United States and overseas.

That eventually grew into a speaking platform. Forney estimates he has told his 9/11 story more than 250 times over the past 25 years.

 It allows me to get it off my chest,  Forney said.  And it allows me to feel like I'm actually doing something good for people. 

Forney believes sharing firsthand accounts has become even more important as a generation that was not alive on Sept. 11, 2001, reaches adulthood.

He hopes his story can help preserve what happened and counter misinformation as the attacks move further into history.

A receipt frozen in time

That mission is reflected in the box of memorabilia Forney has kept through the years.

Inside are newspapers, magazines, letters from schoolchildren and other pieces of his life before and after the attacks.

And now, once again, the ATM receipt.

Forney said he had not seen it in 25 years before discovering it between two books.

The receipt shows he completed the transaction at 8:07 a.m. on Sept. 11, 2001.

Less than 40 minutes later, the North Tower was struck.

 I usually throw these things away,  Forney said.  I don't even know why I kept it. 

Forney says the message he wants future generations to take from his experience is simple:  Never forget. 

That means remembering the people who died, but also the first responders who went toward danger as thousands of others tried to escape.

Forney also sees his survival as a lesson in resilience.

 We can do hard things,  he said.  One of the easiest things to do is what I did coming down those 85 steps - focus one step at a time. 

Twenty-five years after he walked out of the World Trade Center, Forney is still telling his story.

And an ordinary ATM receipt from an ordinary Tuesday morning is now another way to remember the moment before everything changed.