Perry's Victory & International Peace Memorial at Put-in-Bay is closed indefinitely while National Park Service officials determine whether the 352-foot monument is structurally sound.
A nearly 500-pound chunk of granite broke off from the southeast face of the memorial's observation deck Thursday night and dropped about 315 feet to the concrete plaza below. The impact created a 2 1/2-foot wide crater in the plaza, startling a woman who was sitting on a bench nearby.
"She heard what she thought was cannon fire," said Andy Ferguson, superintendent of the memorial, a landmark on South Bass Island in Lake Erie. No one was injured, but debris was scattered across the plaza. The woman notified park rangers, who blocked off the area.
Mr. Ferguson said he chose to close the memorial until it was deemed structurally sound and safe for public use. A structural engineer is expected to arrive at the island today to assess the damage and attempt to determine a cause, he said.
According to the Put-in-Bay Chamber of Commerce, about 200,000 people visit the memorial each year.
National Park Service officials aren't sure whether the break was a result of the severe weather that slammed the region Wednesday and Thursday.
Mr. Ferguson said the monument is struck by lightning frequently, but no one is aware of a lightning strike on Thursday night. He added that a lightning arrestor system was installed in the monument after a strike caused a 200-pound piece of granite to fall in 1920.
"We really don't know what precipitated this," he said of the latest incident.
Each of the 52 granite facing stones that line the four exterior sides of the observation deck is about 7 feet by 3 feet by eight inches and is attached to the monument with metal rods, Mr. Ferguson said. The section that fell was roughly three feet by 3 1/2 feet and 8 inches thick.
Mr. Ferguson estimated the cost of replacing the granite section that fell and repointing the stone facing on the column would be about $4 million.
Constructed between 1912 and 1915 by a commission of nine states and the federal government, Perry's Victory & International Peace Memorial was built to commemorate the American naval triumph in the "Battle of Lake Erie" in 1813 and "to inculcate the lessons of international peace by arbitration and disarmament."
On September 10, 1813, Commodore Oliver Hazard Perry led a group of American ships that defeated and captured a British squadron of warships on Lake Erie several miles west of Put-in-Bay. The battle, fought during the War of 1812, secured control of Lake Erie for the United States and enabled General William Henry Harrison to conduct a successful invasion of British-controlled Canada.
The dual victories gave America the upper hand in negotiations that ended the war with the signing of the Treaty of Ghent in 1814.
The Perry monument is the only peace memorial within the National Parks Service. It was closed between 1980-82 for major renovation. A visitor's center was opened near the base of the monument in 2002.
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