Lighter Side of News (Jun. 2, 2017) by HallR

Question 10

The mini-theme this week is titled: "For Serious Headbangers Only". Here we go. The Wacken Open Air festival in Schweslig-Holstein, Germany is a major annual heavy metal music event. In addition to Megadeath as headliners, for this year's festival organizers' have constructed a 4-mile long underground pipeline to transport what liquid?