The box hangs on a wall at the 9/11 memorial preview site.
Suzy Brown checks the memorial donation box all day. On this one day, it was filled not with coins, but hundred dollar bills.
She counted them, freaked and reached out to the boss.
"So it was Tuesday night. I was watching the Yankee game and I get an email," Joe Daniels said. "Someone left $10,000 cash anonymously in our donation box!"
Memorial officials believe the money was slipped into the box sometime between 5 p.m. - when the box was last checked - and 7 p.m., when the preview site closed.
Officials believe the donation was made by a single person. They say the bills appeared to have been recently withdrawn from the bank.
Word travelled fast and the staff members at the 9/11 memorial preview site were over the moon and so were tourists!
"It's amazing! To hear of someone doing that, great," one woman, a member of a choir group from Ireland, said.
Emotional reaction that floored us came from a man visiting from Munich, Germany.
"American generosity," the man said, almost in tears. "American generosity. I've seen it from the post war period on."
Daniels said officials would love to know the donor's name so they could say thank you.