from Wikipedia, March 11, 2007

The Gundestrup cauldron is a richly decorated silver vessel, thought to date from the La Tène Period in the 2nd or 1st century BC. It was found in a peat bog near Gundestrup in Himmerland, Denmark in 1891. It is now kept in the National Museum of Denmark in Copenhagen.

The decorations on the walls of the cauldron depict Celtic deities and rituals. Because of these, and because of the size of the vessel (diameter 69 cm, height 42 cm), it is thought to have been used for sacrificial purposes of the druidic religion.