© Pendle Forest History Group 2010 webservices from webfactorynorthwest.co.uk Investigations on the Rigg of England page 1  Spen Brook looking towards Noggarth. Pre medieval Boulder wall located on Noggarth Top above Dimpenley Pre medieval Boulder wall located on Noggarth Top above Dimpenley. Investigations at Spen Brook and Noggarth Top Pre medieval Boulder wall located on Noggarth Top above Dimpenley