According to some sources, the Knights Templars discovered the Holy Grail at the Temple in Jerusalem, took it away, and hid it. If this is true, its location is still unknown. The story of the Knights Templars forms part of the basis of the book The DaVinci Code by Dan Brown.

There is no archaeological or historical evidence to suggest that the Holy Grail is currently in Jerusalem, or that it even exists as a physical object. In Christian tradition, the Grail is the vessel used by Jesus at the Last Supper, but the "Grail Quest" is largely a product of 12th-century Arthurian literature rather than biblical scripture. While Jerusalem is the site of the Last Supper (the Cenacle), any wooden or ceramic cup used would have likely decayed or been lost over two millennia. Many legends claim the Grail was taken to Europe by Joseph of Arimathea, leading to famous "candidates" like the Valencia Chalice in Spain or the Genoa Cup in Italy. While Jerusalem is home to countless genuine holy relics and historical sites, the "Holy Grail" remains a figure of myth, symbolism, and medieval romance rather than a documented artifact sitting in a vault within the city. Most historians view it as a metaphorical "spiritual prize" rather than a tangible item to be found.