Eighty percent of the Gateway Arch in St. Louis, Mo., was built in Warren.

And with the 50th anniversary of the Arch approaching next month, event organizers are looking to honor the men from Warren County who built it.

According to a letter from the Jefferson National Parks Association, “We are inviting the Boilermakers who built the sections of the Arch at the Pittsburg Des Moines Steel factory in Warren, PA, to join us this year. Several of them plan to travel from Pennsylvania for this event, and we’re excited to include them in the festivities.”

Any of the Builders looking to make the trip is asked to RSVP by the middle of this month for the Oct. 28 event.

Officials with the Association ask of the builders who go to “bring along any special memorabilia or pictures of the Arch construction that you’d like to share with the public.”

“There were approximately 280 men, about 200 of which were hired for the duration of the Arch build-around three years,” said Ed Atwood, who will be making the trip with some of the Boilermakers. “The beginning shop complement was about 80 men when PDM purchased the shop from Hammond Iron Works.”

According to the National Park Service, each leg of the arch is a “double-walled equilateral triangle with a hollow core 40 feet wide at the base, tapering to 15 1/2 feet at the top.” The inside is made of three-eights inch thick carbon steel, 1 3/4 inches at the corners. “The outside surface was fabricated from 900 tons of polished stainless steel in panels 1/4 inch thick, varying in size from 6 x 18 feet to 6 x 5 1/2 feet. The outer and inner walls were fabricated in sections and bolted together at the Pittsburgh and Warren, Pennsylvania, plants of the Pittsburgh-Des Moines Steel Company, steel fabricators and erectors for the Arch.”

The completed sections were then shipped to St. Louis via rail.

And the legacy of the work done here will be remembered at the “Meet the Builders” event on Oct. 28 50 years to the day of the Arch’s completion.

“It will be an important event for these people to be recognized at that time, and great for Warren to be known at the ‘birthplace of the Arch,'” said Atwood.