The "Azure Window" jutting off Malta's Gozo Island is printed on innumerable Instagram posts and travel brochures. It was also featured in movies and TV shows.
Local resident Roger Chessell was there when the iconic arch collapsed. "There was a big raging sea beneath the window," he told the Times of Malta.
"Suddenly, the arch collapsed into the sea with a loud whoomph, throwing up a huge spray. By the time the spray had faded, the stack had gone too."
Malta's Prime Minister Joseph Muscat called the news "heartbreaking."
"Reports commissioned over the years indicated that this landmark would be hard hit by unavoidable natural corrosion," he said on Twitter. "That sad day has arrived."
In 2013, a study said that the rock formation would inevitably collapse but that it would "likely survive for 'decades' to come," the Times of Malta reported.
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