U.S. military bases around the world marked the 25th anniversary of the Sept. 11 terrorist attacks with solemn ceremonies, stair climbs and other physical challenges honoring victims and first responders.

Stars and Stripes spent recent weeks speaking with Americans impacted by the 9/11 attacks — those who were in the Pentagon when it was struck, those who enlisted in the aftermath and some who went to war seeking revenge for the attack.

“She was so happy,” Kathy Dillaber says about the last vision she had of her sister, Patty Mickley, on Sept. 11, 2001. Mickley was one of the 184 people who died that day in the terrorist attack on the Pentagon.

“The attacks of 9/11 created a generation of Gold Star families,” said Kimberly Hazelgrove, an Army intelligence analyst whose husband died in Iraq in 2004.

The visitor center will keep the stories from the 9/11 attacks at the Pentagon alive for younger generations of Americans who do not remember or were not yet born.

U.S. senators discuss President Barack Obama’s announcement to begin withdrawing troops from Afghanistan during their visit on Independence Day in this 2011 Stars and Stripes photo.

A doctor injects a local anesthetic into a soldier’s gums at the Bulwark ‘04 exercise in Bulgaria in this 2004 Stars and Stripes photo.

Local and military leaders from the U.S., Australia and Japan, in town for Talisman Sabre drills, layed wreaths at the Bowen War Memorial in Australia in this 2019 Stars and Stripes photo.

President Barack Obama speaks on the 15th anniversary of the 9/11 terror attacks at the Pentagon in this 2016 Stars and Stripes photo.

Two soldiers man a guard post at the Range 54 camp in Sinjar, Iraq, in this 2003 Stars and Stripes photo.

A notice posted at a checkout aisle at the Vogelweh commissary, in this 2011 Stars and Stripes photo, informs customers that magazines and most newspapers will no longer be sold in commissaries overseas.

Visitors to the Manila American Cemetery and Memorial look at a map featuring the Battle of Midway in this 2009 Stars and Stripes photo.

Service members cheer as they hoist a boy holding a newspaper up onto their shoulders in this 1961 Stars and Stripes photo.

The Pentagon agency responsible for recovering America’s war dead is prepared to send teams back into North Korea for the first time in two decades if renewed diplomacy between President Donald Trump and Kim Jong Un opens the door.

Col. Alan Smith, director of military member support for the National Committee for Employer Support of the Guard and Reserve, helps a hotline caller in this 2003 Stars and Stripes photo.

Capt. Warren Cusick of the 160th Forward Surgical Team explains to doctors at a maternity clinic in Niger how to handle the units of blood that the U.S. soldiers delivered in this 2005 Stars and Stripes photo.

The Hershel Woody Williams National Medal of Honor Monument Location Act authorizes the placement of a permanent sculpture in the nation’s capital to commemorate individuals who’ve been awarded the military’s highest honor for valor in action.

Secretary of Defense Ash Carter talks to U.S. Marines and Air Force personnel assigned to Moron Air Base, Spain, in this 2015 Stars and Stripes photo.

Members of the 233rd Military Police Company, a National Guard unit from Springfield, Ill., relax on top of their Humvee in this 2004 Stars and Stripes photo.