One of the largest museums in the world is The British Museum. It has over 8 million exhibits in its resources, but only 1 percent of them are exhibited.

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It has nothing to do with any conspiracies or unexplained paranormal phenomena. The amount of exhibition space is simply limited enough to allow approximately 80.000 exhibits to be shown at the same time. Fortunately, in the age of digitization, more and more of the British Museum's treasures are being digitized. In 2020, 4.5 million of them were made available online.