In Schindler's List (1993), a woman says a story:
The trains arrived and the people were driven out with clubs. They were lined up in front of two big warehouses. One was marked "Cloak Room," and the other "Valuables." And there they were made to undress. A Jewish boy handed them pieces of string to tie their shoes together. They shaved their hair. They told them it was needed to make something special for U-boat crews. And then they were herded down a big corridor to bunkers with Stars of David on the doors and signs that said "Bath and Inhalation Room."
Why "down a" instead of "down from"?