The chalice is made of agate, gold, and onyx, and has been in the church since the 11th century. Historians have studied it for three years, and are confident in their conclusion that this is the cup Jesus drank from before he died.
The cup is dated to have been made between 200 B.C. and 100 A.D. and Jesus is believed to have died around 30 A.D. The researchers, Margarita Torres and Jose Manuel Ortega del Rio, say they do not know where the cup was for the first 400 years.
According to ancient parchments, Muslims took the chalice to Cairo and then it was given away. Eventually, it came into possession of Spanish King Ferdinand of Castile and remained in Spain.
The chalice is being moved to a larger space to accommodate the masses of pilgrims coming to see the cup.