
Bolivar Arellano snapped this terrifying shot of the South Tower collapsing. He told The Huffington Post, “Suddenly you could hear a loud explosion, dry like the sound of piercing metal, and then ‘trac, trac, trac.’ The tower was reducing floor by floor like a house of cards. I managed to take one picture and ran.”

This startling juxtaposition of a pregnant woman and the burning World Trade Center has an unsettling power. The woman is Isabel Daser Bessler, a German citizen who was 32 at the time, and her baby came along less than a month later. The photo, meanwhile, was taken by a colleague of Bessler’s, although she can’t remember whom.

This next photo was taken by professional photographer Patricia McDonough. It’s a view from her living room window in an apartment four blocks from the Twin Towers. After taking some photos, McDonough rushed to the scene with first-aid equipment to offer what help she could.