ST. LOUIS (AP) — The Gateway Arch in St. Louis is celebrating its 48th birthday today (Oct. 28).

A party to mark the event on Monday will include a chance to meet the workers who built the monument, which is the world's tallest arch. The public will be able to hear the stories of iron workers, electricians, sheet-metal workers and others who helped complete the Arch.

KSDK reports workers put the final piece of the Arch in place on Oct. 28, 1965. The monument opened to the public on June 10, 1967.

The National Park Service will host the monument's builders in the visitor center below the Arch from 10 a.m. to 11:30 a.m. Monday. The event is free.