Disney-owned National Geographic has slated a six-part docuseries from UK-based 72 Films, commemorating the 20th anniversary of the 9/11 terrorist attacks on the United States, for late August.

9/11: One Day in America has filmmaking team Dan Lindsay and T.J. Martin (L.A. 92, Undefeated) on board as executive producers. The series chronicles the events of the day — the attacks on New York City, Washington DC and Pennsylvania — through first-person accounts from first responders and survivors. The production team sifted through 951 hours of archival footage — some of it rare and previously unused — and over the course of three years, conducted 235 hours worth of interviews with 64 individuals for the final product.

The first episode of the series had its premiere at the Tribeca Film Festival in June, and the series was also an official selection for AFI Docs and Sheffield Doc/Fest.

It will air over four consecutive nights on National Geographic beginning on August 29, with episodes available the next day via Hulu.

“We all remember exactly where we were on Sept. 11, 2001. Amidst the tragedy, chaos and sadness, what we also remember are the incredible feats of heroism, selflessness and humanity on display that day,” said Courteney Monroe, president, National Geographic Content in a statement.

David Glover, co-founder of 72 Films and EP on the series, added that the project “offers hope that through immense difficulty, we can rise above when we work together.”

Besides Glover, Martin and Lindsay, Carolyn Payne exec produces for Nat Geo. Caroline Marsden is series producer for 72 Films. The series is directed by Daniel Bogado and edited by Chris Nicholls, Audinga Kucinskaite, Dan Lavender and Sam Bergson. Music is composed by David Schweitzer.

(Picture: courtesy of 21st Century Fox. Library of Congress: Carol M. Highsmith)