Martin Elbourne had her first job here, what grade was the House listed as?
Martin Elbourne:  His first job, at age fifteen, was working for the local stately home Knebworth House which in the mid-seventies became the biggest venue in the United Kingdom for outdoor shows and hosted bands such as Led Zeppelin, The Rolling Stones and Pink Floyd. Knebworth House:  It is a Grade II* listed building.
Grade II