As New York City braces for Irene's wrath, we remember one of the only recorded hurricanes to touch directly over modern Manhattan.

It was September 3rd, 1821 and within one hour the tides rose 13 feet as the east and west rivers converged on each other downtown, as far north as Chinatown. According to the latest census figures, just over 8 million people currently live inside New York City. In 1821, that number stood at 152,000.

A stroke of luck hit the city as the hurricane came through at low tide, something historians believe kept everything north of Canal Street safe from massive flooding. Ships just to the east of Manhattan were blown ashore onto Long Island, and in one case, killed 17 people as their vessel sank.

Although not a hurricane, the West Indian Cyclone in 1893 was just as vicious. According to the WSJ, it "carried sailing ships to Sixth Avenue, created a river on Canal Street that briefly connected the East River and the Hudson, swept much of Coney Island into the sea and entirely destroyed a barrier beach called Hog Island that once lay south of the Rockaways in Queens."

It turns out New York City isn't blessed with strong geological defenses to massive storm surges. The city sits inside the right angle of land formed by New Jersey and Long Island and according to Mike Lee, a former Director of Watch Command at New York City's Office of Emergency Management, told the New York Press, "Hurricanes do not like right angles, they allow water to accumulate and pile up."

"When we see a category-3 storm making landfall in Florida, it may only have a 12-13-foot storm surge," Lee says. "For us here, a category-1 storm can give us 12 feet of storm surge."

Republished with permission from BusinessInsider.com. Authored by Zachary Lichaa. Photo via Shutterstock.com.