A medieval monument in England underwent a dramatic cleaning when a high pressure tanker sucked up about 25 tons of pigeon poo from the historic structure.
Measuring almost three feet deep, the bird droppings built up over decades inside the towers of the roofless 14th-century Landgate Arch in Rye, East Sussex.
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Since there is no public access to the towers, the massive, mushy mess went unnoticed until last month, when members of the Rother District Council, which owns the ancient monument, made the stomach-turning finding.
"Whilst we've removed other massive blockages such giant fatbergs in sewers, we have never seen such a monumental mass of festering feces before," Mike Walker, managing director for CountyClean Environmental Services, appointed to clean the towers last week, said in a statement.
He added that the build up behind the doors was such that cleaners had to force the doors open.
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"Once inside, it was like walking on a giant chocolate cake and the smell was awful –- even through a facemask," he said.
Had the guano not been removed, it would have continued to accumulate and cause structural damage to the monument. The acidic pigeon poo can damage stonework seriously.
The clean-up took four days using a powerful custom built machine.
"The machine provides high powered vacuum suction through hoses as well as high pressure water jetting," Graeme Sanderson at CountyClean Environmental Services told Discovery News.
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The only survivor of four fortified gateways, the Landgate Arch dates to 1329, in the early years of the reign of King Edward III. It features a chamber over the arch and was built to protect Rye from marauding French invaders.
Pigeons are often perched in the alcoves of the iconic Arch, which is still the only vehicular route into the medieval center of Rye and one of the town's most photographed sights.
Image: Sucking up the pigeon droppings from the iconic Landgate Arch in Rye. Credit: Graeme Sanderson/ CountyClean Environmental Services.