On Sunday — two days shy of the 17th anniversary of the Sept. 11, 2001, terror attacks on the World Trade Center in New York and the Pentagon in Washington, D.C. — firefighters and other supporters will climb the equivalent of 110 stories at Clipper Magazine Stadium in remembrance of the attack.

The number of steps represents the stairs to the top of the Twin Towers, which fell on 9/11, killing 343 Fire Department of the City of New York  firefighters who were responding to the call.

The National Fallen Firefighters Foundation holds 9/11 Memorial Stair Climb events throughout the country. This will be the eighth year for the Lancaster event.

Last year, nearly 370 men, women and children participated in the local climb.

Firefighters have the choice of wearing turnout gear and carrying their equipment, or wearing regular clothes while they walk. They pause for a silent moment twice — at 9:59 and 10:28 a.m., the times at which the two towers fell.

Participants receive a photo and badge of one of the fallen heroes of Sept. 11th — including 343 firefighters, 37 Port Authority officers, 23 New York police officers and 10 EMS workers who died in the collapse.

The walk this year will begin at 9 a.m. Sunday. Climbers are asked to arrive at the stadium between 8 and 9 a.m.

The walk typically takes about 90 minutes to complete.

Also this year, organizers will hold a silent auction for a framed poster of “The Better Angels: The Firefighters of 9/11” by Dawn Siebel. The poster features oil portraits of each of the 343 firefighters who died.

Proceeds from the auction will benefit the National Fallen Firefighters Foundation.

For more information, visit lancasterstairclimb.org.