The 110-foot-tall structure sticks out like a sore thumb. The windowless metal building on Douglas Road in Rancho Cordova is rectangular in shape with cell phone antennas bolted to the corners.

It’s almost alien.

Smaller buildings hide in its shadow and the fading white paint is a stark contrast to the golden-colored grass fields that surround it.

The words “Security Park” are painted on one side, but the building is far from secure as 86-year-old Don Brincka walks in the giant sliding door.

“The missile used to stand up here. There was room for two,” Brincka said.

Brincka is what you call a rocket testing engineer. From 1958 to 1970 he worked inside this building for the Douglas Aircraft Company. His main job: testing the Saturn V rocket.

To date the Saturn V rocket is the most powerful rocket to leave earth’s orbit. It’s also the same rocket that took man to the moon.

Brincka and about 50 other people played a crucial role in testing electrical and mechanical functions of Saturn V rockets.

"We had no room for failure,” he said. “No questions about it – it had to work!"

Forty-eight years ago, the Rancho Cordova test facility was a top secret sophisticated rocket hanger. Today, it’s used as a welding shop for a building contractor.

“This building was built specifically for the Saturn V,“ Brincka said.

The last Saturn V rocket launched in 1972. The Douglas Aircraft Company lost the bid to test NASA’s next rocket.

Today, the Rancho Cordova test facility is part of an industrial park. These days the security is not as tight as it used to be in the 1960, so Brincka and about a dozen of his former co-workers are visiting the former rocket hanger to reminisce on old memories.

"When you are immersed in the middle of the subject, you don't realize the scope of it,” Brincka said. “It’s only later that you realize it was a really big issue."

The Saturn V rocket was made up of three parts. Brincka and his team tested the third and final rocket stage that pushed astronauts from earth's orbit to the moons orbit.

“The computer that we would use would fill up an entire room,” Brincka said. “There was a whole mess of wires.”

It was no easy task getting the 3-stage section of the Saturn V rocket to Rancho Cordova. First it was built in Los Angeles. Then a specially designed jet flew the rocket to Mather Airport. From there it was trucked to the test facility where a team of mechanics took over.

A total of 13 Saturn V rockets were launched into space. It still has the highest payload capability of all NASA rockets.

However, that will change in 2019 when NASA launches their new SLS mega rocket, but the work at Rancho Cordova will not be forgotten.

Brincka and all the other former NASA workers have laid the foundation for the next space race: the mission to Mars.