An underground beer pipeline is being laid for the Wacken Open Air (WOA) hard rock festival, which kicks off in northern Germany in August. It is part of a new 7km (four-mile) pipeline network, which organisers say will make the event more eco-friendly. The beer flow rate should reach six glasses every six seconds, thanks to the 35cm (14-inch) diameter pipeline. WOA is one of the world's biggest heavy metal events. The line-up will include Megadeth, Alice Cooper and Trivium.

Read more at www.bbc.com