Gov. Josh Shapiro (D-PA) announced that Shanksville, Pennsylvania, would unveil the final marker on the 9/11 National Memorial Trail to honor the heroes of the Sept. 11 terrorist attacks.

The marker will be the final sign placed in Pennsylvania to complete the over 1,500-mile trail that was created to commemorate the nearly 3,000 people who lost their lives when al Qaeda attacked the United States 25 years ago. The memorial trail connects New York City, Shanksville, and the Pentagon — the three sites where the terrorist-hijacked planes crashed — while stopping at other historically significant markers along the way.