A rental truck filled with explosives detonated outside of the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma leaving 168 people dead and more than 500 injured at 9:02 a.m. on April 19, 1995.

Two Oklahoma City businessmen began the OKC Memorial run in 2001, to honor the victims of the bombing.

The 2001 marathon registered less than 5,000 runners. Seventeen years later the event garnered 24,677 participants.

There were over 3,000 volunteers for the event which consisted of a full marathon, a half marathon and a five person relay and garnered runners from every state as well as several foreign countries.

Rounding out the event was the kid's marathon. The children participated along with their school and logged 25 miles in the months before the day of the race. The remaining 1.2 miles are run on race day.

For the second year in a row, employees from the U.S. Army Corps of Engineers, Tulsa District, participated in the relay event, viewing the race as a way to build morale and camaraderie.

Working toward a common goal outside of work becomes a bond for them as co-workers. The Tulsa District's participants for this year's event included Daniel de Robles, Stephen Sewell, Chris West, James Neece and Capt. Brian King. This was the first year for King to participate.

"When my USACE career brought me to Oklahoma, I knew I was coming in as a bit of an outsider," stated De Robles, an area engineer, who came to the Tulsa District from San Antonio in early 2017. "I wanted to connect to the Central Oklahoma Area Office staff as quickly as possible and also wanted to get our staff more involved in the community."

The team finished the relay in 4:06:06, besting their time from the previous year by around 15 minutes. They placed 5th in the government category and 92nd overall.

"Since I am new to the area, getting to participate in the marathon relay gave me an opportunity to see the passion and hospitality of the people of Oklahoma City," said King, project engineer. "It's amazing how they have used such a tragedy to bring the city together."

The early race time did nothing to dampen the spirits of the competitors or the spectators. By 5:30 a.m. a growing crowd already surrounded the starting area. People of all ages were on hand to cheer on their favorite runner.

"Just being there at the start is an incredible site to see," according to Sewell, resident engineer. "There are thousands of people and it is a very intense feeling, being there to support and remember those that passed in the bombing."