Writer Ernst Christmann tried to link the name with a crypt ("Gruft" in German) or a cave.

作家恩斯特·克莱斯特曼努力将这个名字和地窖（德语中的“墓穴”）或洞穴联系在一起。

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Topped with a spectacular lead dome, its crypt is the resting place of Lord Nelson and The Duke of Wellington, among others.

CNN: London: What to see