(CNN) — It has been dubbed "a disaster," a "massacre of the cultural heritage," or, more bluntly, the world's worst restoration project.
The restoration of Spain's Matrera Castle, an ancient Arab fortress in the southern region of Andalucia, has outraged locals and historians, the Spanish cultural heritage group Hispania Nostra said.
"The tower has nothing to do with the original, or even with a medieval castle," Hispania Nostra Vice President Carlos Morenes told CNN. "It's a sort of modern tower, which has horrified and angered locals.
"It's a scandal, and people have almost unanimously rejected it," he added.
Built on a hill near the town of Villamartin, the 9th century fortress is a privately owned site of cultural interest.
The recently completed project was aimed at shoring up the castle's tower, which partly collapsed three years ago. New materials were used to protect the ruins of the three-meter thick walls and give the tower its original shape and dimensions.
"They have called in builders rather than restorers," one of the interviewees said. "As we say here, they have cocked it up."
The project was lambasted on social media.
"The Matrera Castle (Cadiz) before and after its restoration. What a blunder..."
"Matrera Castle, Cadiz, 13th century. When you call builders rather than restorers."
The project has been defined as the new "Ecce Homo," a Spanish painting botched when an elderly churchgoer tried to restore it.
The original "Ecce Homo" (L), the deteriorated version (C) and Cecilia Gimenez's restored version.
"What the s*** have they done to the Matrera Castle in Cadiz? And we were surprised by the Ecce Homo?" said one social media user, Estefi.
The architect behind the restoration project did not immediately respond to a request for comment.
According to Spanish paper ABC, he said the project was aimed at preserving the part of the building still standing and making it look as similar to the original as possible. He explained the difference between original and new materials, saying it's against Spanish law to imitate the original structure.
An argument that does not persuade Hispania Nostra.
"No words are needed when you see the pictures," the group said in a statement.