The incident happened on Church Street and Park Place just before 5 p.m.
Police say the victim, a woman in her 50s, was walking down the street with her husband when the hammock blew off a fifth-floor terrace and struck her in the back and back of the head. Sources say the couple are tourists from England.
The full-size hammock was in one piece on the sidewalk, only cracked, and authorities say they are lucky they didn't bear the full brunt of the furniture.
"I was right across the street, clocked out, eating food, and next thing you know, boom," a witness named Serena said. "You hear something loud and collapsed, and everybody is looking across the street. I come to see the lady, she had gotten hit, she was on the floor. She looked pretty banged up, but she wasn't bleeding, so I guess that's the best part."
Eyewitnesses say a stranger gave the victim a red umbrella for shelter from the rain.
Authorities say the victim was conscious at the scene and was taken to Bellevue Hospital in fair condition. The woman's husband was not injured.
Workers from the TriBeCa House, a luxury rental building near City Hall, eventually carried the hammock back inside.
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